Doc: pre & post incremente/decrement

Also made a litle change to scanner function moveOn(): now it moves on
the last char passed and only if there are more than one chars.

dict-type.go

@@ -33,7 +33,7 @@ func NewDict(dictAny map[any]any) (dict *DictType) {
 }
 
 func newDict(dictAny map[any]*term) (dict *DictType) {
-	// TODO Change wi a call to NewDict()
+	// TODO Change with a call to NewDict()
 	var d DictType
 	if dictAny != nil {
 		d = make(DictType, len(dictAny))

doc/Expr.adoc

@@ -439,8 +439,8 @@ _non-empty-list_ = "**[**" _any-value_ {"**,**" _any-value_} "**]**" +
 
 | [blue]`+` | _Join_ | Joins two lists | [blue]`[1,2] + [3]` -> _[1,2,3]_
 | [blue]`-` | _Difference_ | Left list without elements in the right list  | [blue]`[1,2,3] - [2]` -> _[1,3]_
-| [blue]`>>` | _Front insertion_ | Insert an item in front | [blue]`0 >> [1,2]` -> _[0,1,2]_
+| [blue]`+>` | _Front insertion_ | Insert an item in front | [blue]`0 +> [1,2]` -> _[0,1,2]_
-| [blue]`<<` | _Back insertion_ | Insert an item at end | [blue]`[1,2] << 3` -> _[1,2,3]_
+| [blue]`<+` | _Back insertion_ | Insert an item at end | [blue]`[1,2] <+ 3` -> _[1,2,3]_
 | [blue]`[]` | _Item at index_ | Item at given position | [blue]`[1,2,3][1]` -> _2_
 | [blue]`in` | _Item in list_ | True if item is in list | [blue]`2 in [1,2,3]` -> _true_ +
 [blue]`6 in [1,2,3]` -> _false_
@@ -735,14 +735,17 @@ NOTE: These operators have a high priority, in particular higher than the operat
 The table below shows all supported operators by decreasing priorities.
 
 .Operators priorities
-[cols="^2,^2,^2,^5,^6"]
+[cols="^3,^2,^2,^5,^6"]
 |===
-| Priority | Operators     | Position | Operation | Operands and results
+| Priority | Operator     | Position | Operation | Operands and results
 
 .2+|*ITEM*| [blue]`[`...`]` | _Postfix_ | _List item_| _list_ `[`  _integer_ `]` -> _any_
 | [blue]`[`...`]` | _Postfix_ | _Dict item_ | _dict_ `[` _any_ `]` -> _any_
-.2+|*INC*| [blue]`++` | _Postfix_ | _Post increment_| _integer-variable_ `++` -> _integer_
+.5+|*INC/DEC*| [blue]`++` | _Postfix_ | _Iterator next item_ | _iterator_ `++` -> _any_
-| [blue]`++` | _Postfix_ | _Next item_ | _iterator_ `++` -> _any_
+| [blue]`++` | _Postfix_ | _Post increment_| _integer-variable_ `++` -> _integer_
+| [blue]`++` | _Prefix_ | _Pre increment_ | `++` _integer-variable_ -> _integer_
+| [blue]`--` | _Postfix_ | _Post decrement_ | _integer-variable_ `--` -> _integer_
+| [blue]`--` | _Prefix_ | _Pre decrement_ | `--` _integer-variable_ -> _integer_
 .3+|*DEFAULT*| [blue]`??` | _Infix_ | _Default value_| _variable_ `??` _any-expr_ -> _any_
 | [blue]`?=` | _Infix_ | _Default/assign value_| _variable_ `?=` _any-expr_ -> _any_
 | [blue]`?!` | _Infix_ | _Alternate value_| _variable_ `?!` _any-expr_ -> _any_
@@ -751,13 +754,17 @@ The table below shows all supported operators by decreasing priorities.
 .3+|*SIGN*| [blue]`+`, [blue]`-` | _Prefix_ | _Change-sign_| (`+`\|`-`) _number_ -> _number_
 | [blue]`#` | _Prefix_ | _Lenght-of_ | `#` _collection_ -> _integer_
 | [blue]`#` | _Prefix_ | _Size-of_ | `#` _iterator_ -> _integer_
+.2+|*BIT SHIFT*| [blue]`<<` | _Infix_ | _Left-Shift_ | _integer_ `<<` _integer_ -> _integer_
+| [blue]`>>` | _Infix_ | _Right-Shift_ | _integer_ `>>` _iterator_ -> _integer_
 .2+|*SELECT*| [blue]`? : ::` | _Multi-Infix_ | _Case-Selector_ | _any-expr_ `?` _case-list_ _case-expr_ `:` _case-list_ _case-expr_ ... `::` _default-expr_ -> _any_
 | [blue]`? : ::` | _Multi-Infix_ | _Index-Selector_ | _int-expr_ `?` _case-expr_ `:` _case-expr_ ... `::` _default-expr_ -> _any_
 .1+|*FRACT*| [blue]`:` | _Infix_ | _Fraction_ | _integer_ `:` _integer_ -> _fraction_
-.5+|*PROD*| [blue]`*` | _Infix_ | _Product_ | _number_ `*` _number_ -> _number_
+.7+|*PROD*| [blue]`*` | _Infix_ | _Product_ | _number_ `*` _number_ -> _number_
 | [blue]`*` | _Infix_ | _String-repeat_ | _string_ `*` _integer_ -> _string_
 | [blue]`/` | _Infix_ | _Division_ | _number_ `/` _number_ -> _number_
 | [blue]`./` | _Infix_ | _Float-division_ | __number__ `./` _number_ -> _float_
+| [blue]`/` | _Infix_ | _Split_ | _string_ `/` _string_ -> _list_
+| [blue]`/` | _Infix_ | _Split_ | _string_ `/` integer -> _list_
 | [blue]`%` | _Infix_ | _Integer-remainder_ | _integer_ `%` _integer_ -> _integer_
 .6+|*SUM*| [blue]`+` | _Infix_ | _Sum_ | _number_ `+` _number_ -> _number_
 | [blue]`+` | _Infix_ |  _String-concat_ | (_string_\|_number_) `+` (_string_\|_number_) -> _string_
@@ -765,9 +772,10 @@ The table below shows all supported operators by decreasing priorities.
 | [blue]`+` | _Infix_ |  _Dict-join_ | _dict_ `+` _dict_ -> _dict_
 | [blue]`-` | _Infix_ | _Subtraction_ | _number_ `-` _number_ -> _number_
 | [blue]`-` | _Infix_ | _List-difference_ | _list_ `-` _list_ -> _list_
-.3+|*BINARY*| [blue]`&` | _Infix_ | _Binary And_ | _number_ `&` _number_ -> _number_
+.1+|*BITWISE NOT*| [blue]`~` | _Prefix_ | _Binary Not_ | `~` _integer_ -> _integer_
-| [blue]`\|` | _Infix_ | _Binary Or_ | _number_ `\|` _number_ -> _number_
+.1+|*BITWISE AND*| [blue]`&` | _Infix_ | _Binary And_ | _integer_ `&` _integer_ -> _integer_
-| [blue]`~` | _Prefix_ | _Binary Not_ | `~` _number_ -> _number_
+.2+|*BITWISE OR*| [blue]`\|` | _Infix_ | _Binary Or_ | _integer_ `\|` _integer_ -> _integer_
+| [blue]`^` | _Infix_ | _Binary Xor_ | _integer_ `^` _integer_ -> _integer_
 .8+|*RELATION*| [blue]`<` | _Infix_ | _Less_ | _comparable_ `<` _comparable_ -> _boolean_
 | [blue]`\<=` | _Infix_ |  _less-equal_ | _comparable_ `\<=` _comparable_ -> _boolean_
 | [blue]`>` | _Infix_ |  _Greater_ | _comparable_ `>` _comparable_ -> _boolean_
@@ -776,20 +784,54 @@ The table below shows all supported operators by decreasing priorities.
 | [blue]`!=` | _Infix_ |  _Not-equal_ | _comparable_ `!=` _comparable_ -> _boolean_
 | [blue]`in` | _Infix_ |  _Member-of-list_ | _any_ `in` _list_ -> _boolean_
 | [blue]`in` | _Infix_ |  _Key-of-dict_ | _any_ `in` _dict_ -> _boolean_
-.1+|*NOT*| [blue]`not` | _Prefix_ | _Not_ | `not` _boolean_ -> _boolean_
+.1+|*LOGIC NOT*| [blue]`not` | _Prefix_ | _Not_ | `not` _boolean_ -> _boolean_
-.2+|*AND*| [blue]`and` | _Infix_ | _And_ | _boolean_ `and` _boolean_ -> _boolean_
+.2+|*LOGIC AND*| [blue]`and` | _Infix_ | _And_ | _boolean_ `and` _boolean_ -> _boolean_
 | [blue]`&&` | _Infix_ | _And_ | _boolean_ `&&` _boolean_ -> _boolean_
-.2+|*OR*| [blue]`or` | _Infix_ | _Or_ | _boolean_ `or` _boolean_ -> _boolean_
+.2+|*LOGIC OR*| [blue]`or` | _Infix_ | _Or_ | _boolean_ `or` _boolean_ -> _boolean_
 | [blue]`\|\|` | _Infix_ | _Or_ | _boolean_ `\|\|` _boolean_ -> _boolean_
-.3+|*ASSIGN*| [blue]`=` | _Infix_ | _Assignment_ | _identifier_ `=` _any_ -> _any_
+.2+|*INSERT*| [blue]`+>` | _Infix_ | _Prepend_ | _any_ `+>` _list_ -> _list_
-| [blue]`>>` | _Infix_ | _Front-insert_ | _any_ `>>` _list_ -> _list_
+| [blue]`<+` | _Infix_ | _Append_ | _list_ `<+` _any_ -> _list_
-| [blue]`<<` | _Infix_ | _Back-insert_ | _list_ `<<` _any_ -> _list_
+.2+|*ASSIGN*| [blue]`=` | _Infix_ | _Assignment_ | _identifier_ `=` _any_ -> _any_
+4+| _See also the table of special allocation operators below_
 .1+|*BUT*| [blue]`but` | _Infix_ | _But_ | _any_ `but` _any_ -> _any_
 .1+|*RANGE*| [blue]`:` | _Infix_ | _Index-range_ | _integer_ `:` _integer_ -> _integer-pair_
 |===
 
 //^1^ Experimental
 
+.Special assignment perators
+[cols="^2,^2,^4,^6"]
+|===
+| Priority | Operator    | Operation |Equivalent operation
+
+.9+|*ASSIGN*| [blue]`+=` | _Sum & Assign_ | _var_ `\+=` _expr_  +
+short for +
+_var_ `=` _value-of-var_ `+` _expr_
+| [blue]`-=` | _Subtract & Assign_ | _var_ `-=` _expr_  +
+short for +
+_var_ `=` _value-of-var_ `-` _expr_
+| [blue]`*=` | _Multiply & Assign_ | _var_ `\*=` _expr_  +
+short for +
+_var_ `=` _value-of-var_ `*` _expr_
+| [blue]`/=` | _Divide & Assign_ | _var_ `/=` _expr_  +
+short for +
+_var_ `=` _value-of-var_ `/` _expr_
+| [blue]`%=` | _Remainder & Assign_ | _var_ `%=` _expr_  +
+short for +
+_var_ `=` _value-of-var_ `%` _expr_
+| [blue]`&=` | _Bitwise and & Assign_ | _var_ `&=` _expr_  +
+short for +
+_var_ `=` _value-of-var_ `&` _expr_
+| [blue]`\|=` | _Bitwise or & Assign_ | _var_ `\|=` _expr_  +
+short for +
+_var_ `=` _value-of-var_ `\|` _expr_
+| [blue]`<\<=` | _Left shift & Assign_ | _var_ `<\<=` _expr_  +
+short for +
+_var_ `=` _value-of-var_ `<<` _expr_
+| [blue]`>>=` | _Right shift & Assign_ | _var_ `>>=` _expr_  +
+short for +
+_var_ `=` _value-of-var_ `>>` _expr_
+|===
 
 == Functions
 Functions in _Expr_ are very similar to functions available in many programming languages. Currently, _Expr_ supports two types of function, _expr-functions_ and _go-functions_.
@@ -840,7 +882,7 @@ _param-name_ = _identifier_
 
 
 === _Golang_ function definition
-Description of how to define Golan functions and how to bind them to _Expr_ are topics treated in another document that I'll write, one day, maybe.
+Description of how to define Golang functions and how to bind them to _Expr_ are topics covered in another document that I'll write, one day, maybe.
 
 === Function calls
 To call a function, either Expr or Golang type, it is necessary to specify its name and, at least, its required parameters.

doc/Expr.html

@@ -1380,16 +1380,16 @@ dev-expr <span class="nt">--</span> Expressions calculator v1.10.0<span class="o
 <td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">[1,2,3] - [2]</code> &#8594; <em>[1,3]</em></p></td>
 </tr>
 <tr>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&gt;&gt;</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">+&gt;</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Front insertion</em></p></td>
 <td class="tableblock halign-left valign-top"><p class="tableblock">Insert an item in front</p></td>
-<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">0 &gt;&gt; [1,2]</code> &#8594; <em>[0,1,2]</em></p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">0 +&gt; [1,2]</code> &#8594; <em>[0,1,2]</em></p></td>
 </tr>
 <tr>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&lt;&lt;</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&lt;+</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Back insertion</em></p></td>
 <td class="tableblock halign-left valign-top"><p class="tableblock">Insert an item at end</p></td>
-<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">[1,2] &lt;&lt; 3</code> &#8594; <em>[1,2,3]</em></p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock"><code class="blue">[1,2] &lt;+ 3</code> &#8594; <em>[1,2,3]</em></p></td>
 </tr>
 <tr>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">[]</code></p></td>
@@ -1900,16 +1900,16 @@ These operators have a high priority, in particular higher than the operator <co
 <table class="tableblock frame-all grid-all stretch">
 <caption class="title">Table 8. Operators priorities</caption>
 <colgroup>
-<col style="width: 11.7647%;">
+<col style="width: 16.6666%;">
-<col style="width: 11.7647%;">
+<col style="width: 11.1111%;">
-<col style="width: 11.7647%;">
+<col style="width: 11.1111%;">
-<col style="width: 29.4117%;">
+<col style="width: 27.7777%;">
-<col style="width: 35.2942%;">
+<col style="width: 33.3335%;">
 </colgroup>
 <thead>
 <tr>
 <th class="tableblock halign-center valign-top">Priority</th>
-<th class="tableblock halign-center valign-top">Operators</th>
+<th class="tableblock halign-center valign-top">Operator</th>
 <th class="tableblock halign-center valign-top">Position</th>
 <th class="tableblock halign-center valign-top">Operation</th>
 <th class="tableblock halign-center valign-top">Operands and results</th>
@@ -1930,7 +1930,13 @@ These operators have a high priority, in particular higher than the operator <co
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>dict</em> <code>[</code> <em>any</em> <code>]</code> &#8594; <em>any</em></p></td>
 </tr>
 <tr>
-<td class="tableblock halign-center valign-top" rowspan="2"><p class="tableblock"><strong>INC</strong></p></td>
+<td class="tableblock halign-center valign-top" rowspan="5"><p class="tableblock"><strong>INC/DEC</strong></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">++</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Postfix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Iterator next item</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>iterator</em> <code>++</code> &#8594; <em>any</em></p></td>
+</tr>
+<tr>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">++</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Postfix</em></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Post increment</em></p></td>
@@ -1938,9 +1944,21 @@ These operators have a high priority, in particular higher than the operator <co
 </tr>
 <tr>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">++</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Prefix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Pre increment</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code>++</code> <em>integer-variable</em> &#8594; <em>integer</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">--</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Postfix</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Next item</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Post decrement</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>iterator</em> <code>++</code> &#8594; <em>any</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>integer-variable</em> <code>--</code> &#8594; <em>integer</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">--</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Prefix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Pre decrement</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code>--</code> <em>integer-variable</em> &#8594; <em>integer</em></p></td>
 </tr>
 <tr>
 <td class="tableblock halign-center valign-top" rowspan="3"><p class="tableblock"><strong>DEFAULT</strong></p></td>
@@ -1988,6 +2006,19 @@ These operators have a high priority, in particular higher than the operator <co
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code>#</code> <em>iterator</em> &#8594; <em>integer</em></p></td>
 </tr>
 <tr>
+<td class="tableblock halign-center valign-top" rowspan="2"><p class="tableblock"><strong>BIT SHIFT</strong></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&lt;&lt;</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Left-Shift</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>integer</em> <code>&lt;&lt;</code> <em>integer</em> &#8594; <em>integer</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&gt;&gt;</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Right-Shift</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>integer</em> <code>&gt;&gt;</code> <em>iterator</em> &#8594; <em>integer</em></p></td>
+</tr>
+<tr>
 <td class="tableblock halign-center valign-top" rowspan="2"><p class="tableblock"><strong>SELECT</strong></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">? : ::</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Multi-Infix</em></p></td>
@@ -2008,7 +2039,7 @@ These operators have a high priority, in particular higher than the operator <co
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>integer</em> <code>:</code> <em>integer</em> &#8594; <em>fraction</em></p></td>
 </tr>
 <tr>
-<td class="tableblock halign-center valign-top" rowspan="5"><p class="tableblock"><strong>PROD</strong></p></td>
+<td class="tableblock halign-center valign-top" rowspan="7"><p class="tableblock"><strong>PROD</strong></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">*</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Product</em></p></td>
@@ -2033,6 +2064,18 @@ These operators have a high priority, in particular higher than the operator <co
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>number</em> <code>./</code> <em>number</em> &#8594; <em>float</em></p></td>
 </tr>
 <tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">/</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Split</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>string</em> <code>/</code> <em>string</em> &#8594; <em>list</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">/</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Split</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>string</em> <code>/</code> integer &#8594; <em>list</em></p></td>
+</tr>
+<tr>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">%</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Integer-remainder</em></p></td>
@@ -2076,23 +2119,31 @@ These operators have a high priority, in particular higher than the operator <co
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>list</em> <code>-</code> <em>list</em> &#8594; <em>list</em></p></td>
 </tr>
 <tr>
-<td class="tableblock halign-center valign-top" rowspan="3"><p class="tableblock"><strong>BINARY</strong></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><strong>BITWISE NOT</strong></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&amp;</code></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Binary And</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>number</em> <code>&amp;</code> <em>number</em> &#8594; <em>number</em></p></td>
-</tr>
-<tr>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">|</code></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Binary Or</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>number</em> <code>|</code> <em>number</em> &#8594; <em>number</em></p></td>
-</tr>
-<tr>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">~</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Prefix</em></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Binary Not</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><code>~</code> <em>number</em> &#8594; <em>number</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code>~</code> <em>integer</em> &#8594; <em>integer</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><strong>BITWISE AND</strong></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&amp;</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Binary And</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>integer</em> <code>&amp;</code> <em>integer</em> &#8594; <em>integer</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top" rowspan="2"><p class="tableblock"><strong>BITWISE OR</strong></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">|</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Binary Or</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>integer</em> <code>|</code> <em>integer</em> &#8594; <em>integer</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">^</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Binary Xor</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>integer</em> <code>^</code> <em>integer</em> &#8594; <em>integer</em></p></td>
 </tr>
 <tr>
 <td class="tableblock halign-center valign-top" rowspan="8"><p class="tableblock"><strong>RELATION</strong></p></td>
@@ -2144,14 +2195,14 @@ These operators have a high priority, in particular higher than the operator <co
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>any</em> <code>in</code> <em>dict</em> &#8594; <em>boolean</em></p></td>
 </tr>
 <tr>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><strong>NOT</strong></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><strong>LOGIC NOT</strong></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">not</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Prefix</em></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Not</em></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code>not</code> <em>boolean</em> &#8594; <em>boolean</em></p></td>
 </tr>
 <tr>
-<td class="tableblock halign-center valign-top" rowspan="2"><p class="tableblock"><strong>AND</strong></p></td>
+<td class="tableblock halign-center valign-top" rowspan="2"><p class="tableblock"><strong>LOGIC AND</strong></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">and</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>And</em></p></td>
@@ -2164,7 +2215,7 @@ These operators have a high priority, in particular higher than the operator <co
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>boolean</em> <code>&amp;&amp;</code> <em>boolean</em> &#8594; <em>boolean</em></p></td>
 </tr>
 <tr>
-<td class="tableblock halign-center valign-top" rowspan="2"><p class="tableblock"><strong>OR</strong></p></td>
+<td class="tableblock halign-center valign-top" rowspan="2"><p class="tableblock"><strong>LOGIC OR</strong></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">or</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Or</em></p></td>
@@ -2177,23 +2228,27 @@ These operators have a high priority, in particular higher than the operator <co
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>boolean</em> <code>||</code> <em>boolean</em> &#8594; <em>boolean</em></p></td>
 </tr>
 <tr>
-<td class="tableblock halign-center valign-top" rowspan="3"><p class="tableblock"><strong>ASSIGN</strong></p></td>
+<td class="tableblock halign-center valign-top" rowspan="2"><p class="tableblock"><strong>INSERT</strong></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">+&gt;</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Prepend</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>any</em> <code>+&gt;</code> <em>list</em> &#8594; <em>list</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&lt;+</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Append</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>list</em> <code>&lt;+</code> <em>any</em> &#8594; <em>list</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top" rowspan="2"><p class="tableblock"><strong>ASSIGN</strong></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">=</code></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>Assignment</em></p></td>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><em>identifier</em> <code>=</code> <em>any</em> &#8594; <em>any</em></p></td>
 </tr>
 <tr>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&gt;&gt;</code></p></td>
+<td class="tableblock halign-center valign-top" colspan="4"><p class="tableblock"><em>See also the table of special allocation operators below</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Front-insert</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>any</em> <code>&gt;&gt;</code> <em>list</em> &#8594; <em>list</em></p></td>
-</tr>
-<tr>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&lt;&lt;</code></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Infix</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Back-insert</em></p></td>
-<td class="tableblock halign-center valign-top"><p class="tableblock"><em>list</em> <code>&lt;&lt;</code> <em>any</em> &#8594; <em>list</em></p></td>
 </tr>
 <tr>
 <td class="tableblock halign-center valign-top"><p class="tableblock"><strong>BUT</strong></p></td>
@@ -2211,6 +2266,89 @@ These operators have a high priority, in particular higher than the operator <co
 </tr>
 </tbody>
 </table>
+<table class="tableblock frame-all grid-all stretch">
+<caption class="title">Table 9. Special assignment perators</caption>
+<colgroup>
+<col style="width: 14.2857%;">
+<col style="width: 14.2857%;">
+<col style="width: 28.5714%;">
+<col style="width: 42.8572%;">
+</colgroup>
+<thead>
+<tr>
+<th class="tableblock halign-center valign-top">Priority</th>
+<th class="tableblock halign-center valign-top">Operator</th>
+<th class="tableblock halign-center valign-top">Operation</th>
+<th class="tableblock halign-center valign-top">Equivalent operation</th>
+</tr>
+</thead>
+<tbody>
+<tr>
+<td class="tableblock halign-center valign-top" rowspan="9"><p class="tableblock"><strong>ASSIGN</strong></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">+=</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Sum &amp; Assign</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>var</em> <code>+=</code> <em>expr</em> <br>
+short for<br>
+<em>var</em> <code>=</code> <em>value-of-var</em> <code>+</code> <em>expr</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">-=</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Subtract &amp; Assign</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>var</em> <code>-=</code> <em>expr</em> <br>
+short for<br>
+<em>var</em> <code>=</code> <em>value-of-var</em> <code>-</code> <em>expr</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">*=</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Multiply &amp; Assign</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>var</em> <code>*=</code> <em>expr</em> <br>
+short for<br>
+<em>var</em> <code>=</code> <em>value-of-var</em> <code>*</code> <em>expr</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">/=</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Divide &amp; Assign</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>var</em> <code>/=</code> <em>expr</em> <br>
+short for<br>
+<em>var</em> <code>=</code> <em>value-of-var</em> <code>/</code> <em>expr</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">%=</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Remainder &amp; Assign</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>var</em> <code>%=</code> <em>expr</em> <br>
+short for<br>
+<em>var</em> <code>=</code> <em>value-of-var</em> <code>%</code> <em>expr</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&amp;=</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Bitwise and &amp; Assign</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>var</em> <code>&amp;=</code> <em>expr</em> <br>
+short for<br>
+<em>var</em> <code>=</code> <em>value-of-var</em> <code>&amp;</code> <em>expr</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">|=</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Bitwise or &amp; Assign</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>var</em> <code>|=</code> <em>expr</em> <br>
+short for<br>
+<em>var</em> <code>=</code> <em>value-of-var</em> <code>|</code> <em>expr</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&lt;&lt;=</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Left shift &amp; Assign</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>var</em> <code>&lt;&lt;=</code> <em>expr</em> <br>
+short for<br>
+<em>var</em> <code>=</code> <em>value-of-var</em> <code>&lt;&lt;</code> <em>expr</em></p></td>
+</tr>
+<tr>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><code class="blue">&gt;&gt;=</code></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Right shift &amp; Assign</em></p></td>
+<td class="tableblock halign-center valign-top"><p class="tableblock"><em>var</em> <code>&gt;&gt;=</code> <em>expr</em> <br>
+short for<br>
+<em>var</em> <code>=</code> <em>value-of-var</em> <code>&gt;&gt;</code> <em>expr</em></p></td>
+</tr>
+</tbody>
+</table>
 </div>
 </div>
 <div class="sect1">
@@ -2282,7 +2420,7 @@ These operators have a high priority, in particular higher than the operator <co
 <div class="sect2">
 <h3 id="_golang_function_definition"><a class="anchor" href="#_golang_function_definition"></a><a class="link" href="#_golang_function_definition">6.2. <em>Golang</em> function definition</a></h3>
 <div class="paragraph">
-<p>Description of how to define Golan functions and how to bind them to <em>Expr</em> are topics treated in another document that I&#8217;ll write, one day, maybe.</p>
+<p>Description of how to define Golang functions and how to bind them to <em>Expr</em> are topics covered in another document that I&#8217;ll write, one day, maybe.</p>
 </div>
 </div>
 <div class="sect2">
@@ -2461,7 +2599,7 @@ g(@p):any{}`
 </div>
 <div id="footer">
 <div id="footer-text">
-Last updated 2024-12-23 07:20:48 +0100
+Last updated 2025-01-05 12:15:58 +0100
 </div>
 </div>
 </body>

operator-assign.go

@@ -183,6 +183,16 @@ func evalOpAssign(ctx ExprContext, opTerm *term) (v any, err error) {
 				v, err = divValues(opTerm, leftValue, rightValue)
 			case SymPercEqual:
 				v, err = remainderValues(opTerm, leftValue, rightValue)
+			case SymAmpersandEqual:
+				v, err = bitwiseAnd(opTerm, leftValue, rightValue)
+			case SymVertBarEqual:
+				v, err = bitwiseOr(opTerm, leftValue, rightValue)
+			case SymCaretEqual:
+				v, err = bitwiseXor(opTerm, leftValue, rightValue)
+			case SymDoubleLessEqual:
+				v, err = bitLeftShift(opTerm, leftValue, rightValue)
+			case SymDoubleGreaterEqual:
+				v, err = bitRightShift(opTerm, leftValue, rightValue)
 			default:
 				err = opTerm.Errorf("unsupported assign operator %q", opTerm.source())
 			}
@@ -201,4 +211,10 @@ func init() {
 	registerTermConstructor(SymMinusEqual, newOpAssignTerm)
 	registerTermConstructor(SymStarEqual, newOpAssignTerm)
 	registerTermConstructor(SymSlashEqual, newOpAssignTerm)
+	registerTermConstructor(SymPercEqual, newOpAssignTerm)
+	registerTermConstructor(SymDoubleLessEqual, newOpAssignTerm)
+	registerTermConstructor(SymDoubleGreaterEqual, newOpAssignTerm)
+	registerTermConstructor(SymAmpersandEqual, newOpAssignTerm)
+	registerTermConstructor(SymVertBarEqual, newOpAssignTerm)
+	registerTermConstructor(SymCaretEqual, newOpAssignTerm)
 }

operator-binary.go

@@ -1,104 +0,0 @@
-// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
-// All rights reserved.
-
-// operator-binary.go
-package expr
-
-//-------- NOT term
-
-func newBinNotTerm(tk *Token) (inst *term) {
-	return &term{
-		tk:       *tk,
-		children: make([]*term, 0, 1),
-		position: posPrefix,
-		priority: priBinary,
-		evalFunc: evalBinaryNot,
-	}
-}
-
-func evalBinaryNot(ctx ExprContext, opTerm *term) (v any, err error) {
-	var value any
-
-	if value, err = opTerm.evalPrefix(ctx); err != nil {
-		return
-	}
-
-	if IsInteger(value) {
-		i, _ := value.(int64)
-		v = ^i
-	} else {
-		err = opTerm.errIncompatibleType(value)
-	}
-	return
-}
-
-//-------- Binary AND term
-
-func newBinAndTerm(tk *Token) (inst *term) {
-	return &term{
-		tk:       *tk,
-		children: make([]*term, 0, 2),
-		position: posInfix,
-		priority: priBinary,
-		evalFunc: evalBinaryAnd,
-	}
-}
-
-func evalBinaryAnd(ctx ExprContext, self *term) (v any, err error) {
-	var leftValue, rightValue any
-	var leftInt, rightInt int64
-	var lok, rok bool
-
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
-		return
-	}
-
-	leftInt, lok = leftValue.(int64)
-	rightInt, rok = rightValue.(int64)
-
-	if lok && rok {
-		v = leftInt & rightInt
-	} else {
-		err = self.errIncompatibleTypes(leftValue, rightValue)
-	}
-	return
-}
-
-//-------- Binary OR term
-
-func newBinOrTerm(tk *Token) (inst *term) {
-	return &term{
-		tk:       *tk,
-		children: make([]*term, 0, 2),
-		position: posInfix,
-		priority: priBinary,
-		evalFunc: evalBinaryOr,
-	}
-}
-
-func evalBinaryOr(ctx ExprContext, self *term) (v any, err error) {
-	var leftValue, rightValue any
-	var leftInt, rightInt int64
-	var lok, rok bool
-
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
-		return
-	}
-
-	leftInt, lok = leftValue.(int64)
-	rightInt, rok = rightValue.(int64)
-
-	if lok && rok {
-		v = leftInt | rightInt
-	} else {
-		err = self.errIncompatibleTypes(leftValue, rightValue)
-	}
-	return
-}
-
-// init
-func init() {
-	registerTermConstructor(SymTilde, newBinNotTerm)
-	registerTermConstructor(SymAmpersand, newBinAndTerm)
-	registerTermConstructor(SymVertBar, newBinOrTerm)
-}

operator-bitwise.go

@@ -0,0 +1,154 @@
+// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
+// All rights reserved.
+
+// operator-bitwise.go
+package expr
+
+//-------- Bitwise NOT term
+
+func newBitwiseNotTerm(tk *Token) (inst *term) {
+	return &term{
+		tk:       *tk,
+		children: make([]*term, 0, 1),
+		position: posPrefix,
+		priority: priBitwiseNot,
+		evalFunc: evalBitwiseNot,
+	}
+}
+
+func evalBitwiseNot(ctx ExprContext, opTerm *term) (v any, err error) {
+	var value any
+
+	if value, err = opTerm.evalPrefix(ctx); err != nil {
+		return
+	}
+
+	if IsInteger(value) {
+		i, _ := value.(int64)
+		v = ^i
+	} else {
+		err = opTerm.errIncompatibleType(value)
+	}
+	return
+}
+
+//-------- Bitwise AND term
+
+func newBitwiseAndTerm(tk *Token) (inst *term) {
+	return &term{
+		tk:       *tk,
+		children: make([]*term, 0, 2),
+		position: posInfix,
+		priority: priBitwiseAnd,
+		evalFunc: evalBitwiseAnd,
+	}
+}
+
+func bitwiseAnd(opTerm *term, leftValue, rightValue any) (v any, err error) {
+	var leftInt, rightInt int64
+	var lok, rok bool
+
+	leftInt, lok = leftValue.(int64)
+	rightInt, rok = rightValue.(int64)
+
+	if lok && rok {
+		v = leftInt & rightInt
+	} else {
+		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
+	}
+	return
+}
+
+func evalBitwiseAnd(ctx ExprContext, opTerm *term) (v any, err error) {
+	var leftValue, rightValue any
+
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
+		return
+	}
+	v, err = bitwiseAnd(opTerm, leftValue, rightValue)
+	return
+}
+
+//-------- Bitwise OR term
+
+func newBitwiseOrTerm(tk *Token) (inst *term) {
+	return &term{
+		tk:       *tk,
+		children: make([]*term, 0, 2),
+		position: posInfix,
+		priority: priBitwiseOr,
+		evalFunc: evalBitwiseOr,
+	}
+}
+
+func bitwiseOr(opTerm *term, leftValue, rightValue any) (v any, err error) {
+	var leftInt, rightInt int64
+	var lok, rok bool
+
+	leftInt, lok = leftValue.(int64)
+	rightInt, rok = rightValue.(int64)
+
+	if lok && rok {
+		v = leftInt | rightInt
+	} else {
+		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
+	}
+	return
+}
+
+func evalBitwiseOr(ctx ExprContext, opTerm *term) (v any, err error) {
+	var leftValue, rightValue any
+
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
+		return
+	}
+
+	v, err = bitwiseOr(opTerm, leftValue, rightValue)
+	return
+}
+
+//-------- Bitwise XOR term
+
+func newBitwiseXorTerm(tk *Token) (inst *term) {
+	return &term{
+		tk:       *tk,
+		children: make([]*term, 0, 2),
+		position: posInfix,
+		priority: priBitwiseOr,
+		evalFunc: evalBitwiseXor,
+	}
+}
+
+func bitwiseXor(opTerm *term, leftValue, rightValue any) (v any, err error) {
+	var leftInt, rightInt int64
+	var lok, rok bool
+
+	leftInt, lok = leftValue.(int64)
+	rightInt, rok = rightValue.(int64)
+
+	if lok && rok {
+		v = leftInt ^ rightInt
+	} else {
+		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
+	}
+	return
+}
+
+func evalBitwiseXor(ctx ExprContext, opTerm *term) (v any, err error) {
+	var leftValue, rightValue any
+
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
+		return
+	}
+
+	v, err = bitwiseXor(opTerm, leftValue, rightValue)
+	return
+}
+
+// init
+func init() {
+	registerTermConstructor(SymTilde, newBitwiseNotTerm)
+	registerTermConstructor(SymAmpersand, newBitwiseAndTerm)
+	registerTermConstructor(SymVertBar, newBitwiseOrTerm)
+	registerTermConstructor(SymCaret, newBitwiseXorTerm)
+}

operator-fraction.go

@@ -7,7 +7,6 @@ package expr
 //https://www.youmath.it/lezioni/algebra-elementare/lezioni-di-algebra-e-aritmetica-per-scuole-medie/553-dalle-frazioni-a-numeri-decimali.html
 
 import (
-	"errors"
 	"fmt"
 )
 
@@ -41,7 +40,7 @@ func evalFraction(ctx ExprContext, opTerm *term) (v any, err error) {
 		return
 	}
 	if den == 0 {
-		err = errors.New("division by zero")
+		err = opTerm.errDivisionByZero()
 		return
 	}
 

operator-insert.go

@@ -4,15 +4,15 @@
 // operator-insert.go
 package expr
 
-//-------- insert term
+//-------- prepend term
 
-func newInsertTerm(tk *Token) (inst *term) {
+func newPrependTerm(tk *Token) (inst *term) {
 	return &term{
 		tk:       *tk,
 		children: make([]*term, 0, 2),
 		position: posInfix,
-		priority: priAssign,
+		priority: priInsert,
-		evalFunc: evalInsert,
+		evalFunc: evalPrepend,
 	}
 }
 
@@ -21,12 +21,12 @@ func newAppendTerm(tk *Token) (inst *term) {
 		tk:       *tk,
 		children: make([]*term, 0, 2),
 		position: posInfix,
-		priority: priAssign,
+		priority: priInsert,
 		evalFunc: evalAppend,
 	}
 }
 
-func evalInsert(ctx ExprContext, opTerm *term) (v any, err error) {
+func evalPrepend(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
 	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
@@ -40,10 +40,6 @@ func evalInsert(ctx ExprContext, opTerm *term) (v any, err error) {
 		if opTerm.children[1].symbol() == SymVariable {
 			ctx.UnsafeSetVar(opTerm.children[1].source(), v)
 		}
-	} else if IsInteger(leftValue) && IsInteger(rightValue) {
-		leftInt := leftValue.(int64)
-		rightInt := rightValue.(int64)
-		v = leftInt >> rightInt
 	} else {
 		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
 	}
@@ -64,10 +60,6 @@ func evalAppend(ctx ExprContext, opTerm *term) (v any, err error) {
 		if opTerm.children[0].symbol() == SymVariable {
 			ctx.UnsafeSetVar(opTerm.children[0].source(), v)
 		}
-	} else if IsInteger(leftValue) && IsInteger(rightValue) {
-		leftInt := leftValue.(int64)
-		rightInt := rightValue.(int64)
-		v = leftInt << rightInt
 	} else {
 		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
 	}
@@ -94,6 +86,6 @@ func evalAppend(ctx ExprContext, opTerm *term) (v any, err error) {
 
 // init
 func init() {
-	registerTermConstructor(SymInsert, newInsertTerm)
+	registerTermConstructor(SymPlusGreater, newPrependTerm)
-	registerTermConstructor(SymAppend, newAppendTerm)
+	registerTermConstructor(SymLessPlus, newAppendTerm)
 }

operator-iter-value.go

@@ -11,7 +11,7 @@ func newIterValueTerm(tk *Token) (inst *term) {
 		tk:       *tk,
 		children: make([]*term, 0, 1),
 		position: posPrefix,
-		priority: priIterValue,
+		priority: priDereference,
 		evalFunc: evalIterValue,
 	}
 }
@@ -34,5 +34,5 @@ func evalIterValue(ctx ExprContext, opTerm *term) (v any, err error) {
 // init
 func init() {
 	//	registerTermConstructor(SymOpenClosedRound, newIterValueTerm)
-	registerTermConstructor(SymCaret, newIterValueTerm)
+	registerTermConstructor(SymDereference, newIterValueTerm)
 }

operator-post-inc-dec.go

@@ -1,7 +1,7 @@
 // Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
 // All rights reserved.
 
-// operator-post-inc.go
+// operator-post-inc-dec.go
 package expr
 
 // -------- post increment term

operator-pre-inc-dec.go

@@ -0,0 +1,69 @@
+// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
+// All rights reserved.
+
+// operator-pre-inc-dec.go
+package expr
+
+// -------- pre increment term
+
+func newPreIncTerm(tk *Token) *term {
+	return &term{
+		tk:       *tk,
+		parent:   nil,
+		children: make([]*term, 0, 1),
+		position: posPrefix,
+		priority: priIncDec,
+		evalFunc: evalPreInc,
+	}
+}
+
+func evalPreInc(ctx ExprContext, opTerm *term) (v any, err error) {
+	var childValue any
+	if childValue, err = opTerm.evalPrefix(ctx); err != nil {
+		return
+	}
+
+	if IsInteger(childValue) && opTerm.children[0].symbol() == SymVariable {
+		i := childValue.(int64) + 1
+		ctx.SetVar(opTerm.children[0].source(), i)
+		v = i
+	} else {
+		err = opTerm.errIncompatibleType(childValue)
+	}
+	return
+}
+
+// -------- pre decrement term
+
+func newPreDecTerm(tk *Token) *term {
+	return &term{
+		tk:       *tk,
+		parent:   nil,
+		children: make([]*term, 0, 1),
+		position: posPrefix,
+		priority: priIncDec,
+		evalFunc: evalPreDec,
+	}
+}
+
+func evalPreDec(ctx ExprContext, opTerm *term) (v any, err error) {
+	var childValue any
+	if childValue, err = opTerm.evalPrefix(ctx); err != nil {
+		return
+	}
+
+	if IsInteger(childValue) && opTerm.children[0].symbol() == SymVariable {
+		i := childValue.(int64) - 1
+		ctx.SetVar(opTerm.children[0].source(), i)
+		v = i
+	} else {
+		err = opTerm.errIncompatibleType(childValue)
+	}
+	return
+}
+
+// init
+func init() {
+	registerTermConstructor(SymPreInc, newPreIncTerm)
+	registerTermConstructor(SymPreDec, newPreDecTerm)
+}

operator-prod.go

@@ -5,7 +5,6 @@
 package expr
 
 import (
-	"errors"
 	"strings"
 )
 
@@ -69,7 +68,7 @@ func divValues(opTerm *term, leftValue, rightValue any) (v any, err error) {
 		if IsFloat(leftValue) || IsFloat(rightValue) {
 			d := numAsFloat(rightValue)
 			if d == 0.0 {
-				err = errors.New("division by zero")
+				err = opTerm.errDivisionByZero()
 			} else {
 				v = numAsFloat(leftValue) / d
 			}
@@ -78,11 +77,36 @@ func divValues(opTerm *term, leftValue, rightValue any) (v any, err error) {
 		} else {
 			leftInt, _ := leftValue.(int64)
 			if rightInt, _ := rightValue.(int64); rightInt == 0 {
-				err = errors.New("division by zero")
+				err = opTerm.errDivisionByZero()
 			} else {
 				v = leftInt / rightInt
 			}
 		}
+	} else if IsString(leftValue) && IsString(rightValue) {
+		source := leftValue.(string)
+		sep := rightValue.(string)
+		v = ListFromStrings(strings.Split(source, sep))
+	} else if IsString(leftValue) && IsInteger(rightValue) {
+		source := leftValue.(string)
+		partSize := int(rightValue.(int64))
+		if partSize == 0 {
+			err = opTerm.errDivisionByZero()
+		} else {
+			partCount := len(source) / partSize
+			remainder := len(source) % partSize
+			listSize := partCount
+			if remainder > 0 {
+				listSize++
+			}
+			parts := make([]any, 0, listSize)
+			for i := 0; i < partCount; i++ {
+				parts = append(parts, source[i*partSize:(i+1)*partSize])
+			}
+			if remainder > 0 {
+				parts = append(parts, source[len(source)-remainder:])
+			}
+			v = newList(parts)
+		}
 	} else {
 		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
 	}
@@ -121,7 +145,7 @@ func evalDivideAsFloat(ctx ExprContext, floatDivTerm *term) (v any, err error) {
 	if isNumOrFract(leftValue) && isNumOrFract(rightValue) {
 		d := numAsFloat(rightValue)
 		if d == 0.0 {
-			err = errors.New("division by zero")
+			err = floatDivTerm.errDivisionByZero()
 		} else {
 			v = numAsFloat(leftValue) / d
 		}
@@ -146,7 +170,7 @@ func remainderValues(opTerm *term, leftValue, rightValue any) (v any, err error)
 	if IsInteger(leftValue) && IsInteger(rightValue) {
 		rightInt, _ := rightValue.(int64)
 		if rightInt == 0 {
-			err = errors.New("division by zero")
+			err = opTerm.errDivisionByZero()
 		} else {
 			leftInt, _ := leftValue.(int64)
 			v = leftInt % rightInt

operator-shift.go

@@ -0,0 +1,77 @@
+// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
+// All rights reserved.
+
+// operator-shift.go
+package expr
+
+//-------- bit right shift term
+
+func newRightShiftTerm(tk *Token) (inst *term) {
+	return &term{
+		tk:       *tk,
+		children: make([]*term, 0, 2),
+		position: posInfix,
+		priority: priBinShift,
+		evalFunc: evalRightShift,
+	}
+}
+
+func bitRightShift(opTerm *term, leftValue, rightValue any) (v any, err error) {
+	if IsInteger(leftValue) && IsInteger(rightValue) {
+		leftInt := leftValue.(int64)
+		rightInt := rightValue.(int64)
+		v = leftInt >> rightInt
+	} else {
+		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
+	}
+	return
+}
+
+func evalRightShift(ctx ExprContext, opTerm *term) (v any, err error) {
+	var leftValue, rightValue any
+
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
+		return
+	}
+
+	v, err = bitRightShift(opTerm, leftValue, rightValue)
+	return
+}
+
+func newLeftShiftTerm(tk *Token) (inst *term) {
+	return &term{
+		tk:       *tk,
+		children: make([]*term, 0, 2),
+		position: posInfix,
+		priority: priBinShift,
+		evalFunc: evalLeftShift,
+	}
+}
+
+func bitLeftShift(opTerm *term, leftValue, rightValue any) (v any, err error) {
+	if IsInteger(leftValue) && IsInteger(rightValue) {
+		leftInt := leftValue.(int64)
+		rightInt := rightValue.(int64)
+		v = leftInt << rightInt
+	} else {
+		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
+	}
+	return
+}
+
+func evalLeftShift(ctx ExprContext, opTerm *term) (v any, err error) {
+	var leftValue, rightValue any
+
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
+		return
+	}
+
+	v, err = bitLeftShift(opTerm, leftValue, rightValue)
+	return
+}
+
+// init
+func init() {
+	registerTermConstructor(SymDoubleGreater, newRightShiftTerm)
+	registerTermConstructor(SymDoubleLess, newLeftShiftTerm)
+}

parser.go

@@ -409,6 +409,23 @@ func listSubTree(tree *ast, listTerm *term, allowIndeces bool) (root *term, err
 	return
 }
 
+func changePrefix(tk *Token) {
+	switch tk.Sym {
+	case SymMinus:
+		tk.SetSymbol(SymChangeSign)
+	case SymPlus:
+		tk.SetSymbol(SymUnchangeSign)
+	case SymStar:
+		tk.SetSymbol(SymDereference)
+	case SymExclamation:
+		tk.SetSymbol(SymNot)
+	case SymDoublePlus:
+		tk.SetSymbol(SymPreInc)
+	case SymDoubleMinus:
+		tk.SetSymbol(SymPreDec)
+	}
+}
+
 func (parser *parser) parseGeneral(scanner *scanner, ctx parserContext, termSymbols ...Symbol) (tree *ast, err error) {
 	var selectorTerm *term = nil
 	var currentTerm *term = nil
@@ -437,14 +454,16 @@ func (parser *parser) parseGeneral(scanner *scanner, ctx parserContext, termSymb
 
 		//fmt.Println("Token:", tk)
 		if firstToken {
-			if tk.Sym == SymMinus {
+			changePrefix(tk)
-				tk.Sym = SymChangeSign
+			// if tk.Sym == SymMinus {
-			} else if tk.Sym == SymPlus {
+			// 	tk.Sym = SymChangeSign
-				tk.Sym = SymUnchangeSign
+			// } else if tk.Sym == SymPlus {
-			} else if tk.IsSymbol(SymExclamation) {
+			// 	tk.Sym = SymUnchangeSign
-				err = tk.Errorf("postfix opertor %q requires an operand on its left", tk)
+			// } else if tk.IsSymbol(SymStar) {
-				break
+			// 	tk.SetSymbol(SymDereference)
-			}
+			// } else if tk.IsSymbol(SymExclamation) {
+			// 	tk.SetSymbol(SymNot)
+			// }
 			firstToken = false
 		}
 
@@ -452,9 +471,12 @@ func (parser *parser) parseGeneral(scanner *scanner, ctx parserContext, termSymb
 		case SymOpenRound:
 			var subTree *ast
 			if subTree, err = parser.parseGeneral(scanner, ctx, SymClosedRound); err == nil {
-				subTree.root.priority = priValue
+				exprTerm := newExprTerm(subTree.root)
-				err = tree.addTerm(newExprTerm(subTree.root))
+				err = tree.addTerm(exprTerm)
-				currentTerm = subTree.root
+				currentTerm = exprTerm
+				// subTree.root.priority = priValue
+				// err = tree.addTerm(newExprTerm(subTree.root))
+				// currentTerm = subTree.root
 			}
 		case SymFuncCall:
 			var funcCallTerm *term
@@ -478,7 +500,7 @@ func (parser *parser) parseGeneral(scanner *scanner, ctx parserContext, termSymb
 					currentTerm = mapTerm
 				}
 			}
-		case SymEqual, SymPlusEqual, SymMinusEqual, SymStarEqual, SymSlashEqual, SymPercEqual:
+		case SymEqual, SymPlusEqual, SymMinusEqual, SymStarEqual, SymSlashEqual, SymPercEqual, SymAmpersandEqual, SymVertBarEqual, SymDoubleLessEqual, SymDoubleGreaterEqual, SymCaretEqual:
 			currentTerm, err = tree.addToken(tk)
 			firstToken = true
 		case SymFuncDef:
@@ -515,15 +537,12 @@ func (parser *parser) parseGeneral(scanner *scanner, ctx parserContext, termSymb
 					}
 				}
 			} else {
-				// if hasFlag(ctx, allowIndex) {
-				// 	tk.Sym = SymRange
-				// }
 				currentTerm, err = tree.addToken(tk)
-			}
 				if tk.IsOneOfA(SymColon, SymRange) {
 					// Colon outside a selector term acts like a separator
 					firstToken = true
 				}
+			}
 		default:
 			currentTerm, err = tree.addToken(tk)
 		}

scanner.go

@@ -124,6 +124,8 @@ func (scanner *scanner) fetchNextToken() (tk *Token) {
 				tk = scanner.moveOn(SymDoublePlus, ch, next)
 			} else if next == '=' {
 				tk = scanner.moveOn(SymPlusEqual, ch, next)
+			} else if next == '>' {
+				tk = scanner.moveOn(SymPlusGreater, ch, next)
 			} else {
 				tk = scanner.makeToken(SymPlus, ch)
 			}
@@ -167,13 +169,19 @@ func (scanner *scanner) fetchNextToken() (tk *Token) {
 		case '|':
 			if next, _ := scanner.peek(); next == '|' {
 				tk = scanner.moveOn(SymDoubleVertBar, ch, next)
+			} else if next, _ = scanner.peek(); next == '=' {
+				tk = scanner.moveOn(SymVertBarEqual, ch, next)
 			} else {
 				tk = scanner.makeToken(SymVertBar, ch)
 			}
 		case ',':
 			tk = scanner.makeToken(SymComma, ch)
 		case '^':
+			if next, _ := scanner.peek(); next == '=' {
+				tk = scanner.moveOn(SymCaretEqual, ch, next)
+			} else {
 				tk = scanner.makeToken(SymCaret, ch)
+			}
 		case ':':
 			if next, _ := scanner.peek(); next == ':' {
 				tk = scanner.moveOn(SymDoubleColon, ch, next)
@@ -232,11 +240,17 @@ func (scanner *scanner) fetchNextToken() (tk *Token) {
 		case '&':
 			if next, _ := scanner.peek(); next == '&' {
 				tk = scanner.moveOn(SymDoubleAmpersand, ch, next)
+			} else if next, _ = scanner.peek(); next == '=' {
+				tk = scanner.moveOn(SymAmpersandEqual, ch, next)
 			} else {
 				tk = scanner.makeToken(SymAmpersand, ch)
 			}
 		case '%':
+			if next, _ := scanner.peek(); next == '=' {
+				tk = scanner.moveOn(SymPercEqual, ch, next)
+			} else {
 				tk = scanner.makeToken(SymPercent, ch)
+			}
 		case '#':
 			tk = scanner.makeToken(SymHash, ch)
 		case '@':
@@ -265,9 +279,18 @@ func (scanner *scanner) fetchNextToken() (tk *Token) {
 			if next, _ := scanner.peek(); next == '=' {
 				tk = scanner.moveOn(SymLessOrEqual, ch, next)
 			} else if next == '<' {
-				tk = scanner.moveOn(SymAppend, ch, next)
+				scanner.readChar()
+				next2, _ := scanner.readChar()
+				scanner.unreadChar()
+				if next2 == '=' {
+					tk = scanner.moveOn(SymDoubleLessEqual, ch, next, next2)
+				} else {
+					tk = scanner.accept(SymDoubleLess, ch, next)
+				}
 			} else if next == '>' {
 				tk = scanner.moveOn(SymLessGreater, ch, next)
+			} else if next == '+' {
+				tk = scanner.moveOn(SymLessPlus, ch, next)
 			} else {
 				tk = scanner.makeToken(SymLess, ch)
 			}
@@ -275,7 +298,14 @@ func (scanner *scanner) fetchNextToken() (tk *Token) {
 			if next, _ := scanner.peek(); next == '=' {
 				tk = scanner.moveOn(SymGreaterOrEqual, ch, next)
 			} else if next == '>' {
-				tk = scanner.moveOn(SymInsert, ch, next)
+				scanner.readChar()
+				next2, _ := scanner.readChar()
+				scanner.unreadChar()
+				if next2 == '=' {
+					tk = scanner.moveOn(SymDoubleGreaterEqual, ch, next, next2)
+				} else {
+					tk = scanner.accept(SymDoubleGreater, ch, next)
+				}
 			} else {
 				tk = scanner.makeToken(SymGreater, ch)
 			}
@@ -630,9 +660,16 @@ func (scanner *scanner) translate(sym Symbol) Symbol {
 
 func (scanner *scanner) moveOn(sym Symbol, chars ...byte) (tk *Token) {
 	tk = NewToken(scanner.row, scanner.column, scanner.translate(sym), string(chars))
-	for i := 1; i < len(chars); i++ {
+	// for i := 1; i < len(chars); i++ {
+	if len(chars) > 1 {
 		scanner.readChar()
 	}
+	// }
+	return
+}
+
+func (scanner *scanner) accept(sym Symbol, chars ...byte) (tk *Token) {
+	tk = NewToken(scanner.row, scanner.column, scanner.translate(sym), string(chars))
 	return
 }
 

symbol-map.go

@@ -14,7 +14,7 @@ type symbolClass int16
 
 const (
 	symClassOperator symbolClass = iota
-	symClassPostOp
+	symClassCommand
 	symClassIdentifier
 	symClassDelimiter
 	symClassParenthesis
@@ -26,75 +26,85 @@ const (
 type symbolSpec struct {
 	repr   string
 	kind   symbolClass
+	opType termPosition
 }
 
 func init() {
 
 	symbolMap = map[Symbol]symbolSpec{
-		SymUnknown:         {"<unknown>", symClassOther}, //  -1: Unknown symbol
+		SymUnknown:            {"<unknown>", symClassOther, posLeaf},  //  -1: Unknown symbol
-		SymNone:            {"<null>", symClassOther},    //   0: Null value for variable of type symbol
+		SymNone:               {"<null>", symClassOther, posLeaf},     //   0: Null value for variable of type symbol
-		SymError:           {"<error>", symClassOther},   //   1: Error reading from stream
+		SymError:              {"<error>", symClassOther, posLeaf},    //   1: Error reading from stream
-		SymEos:             {"<eos>", symClassOther},     //   2: End of stream
+		SymEos:                {"<eos>", symClassOther, posLeaf},      //   2: End of stream
-		SymMinus:           {"-", symClassOperator},      //   3: '-'
+		SymMinus:              {"-", symClassOperator, posInfix},      //   3: '-'
-		SymMinusEqual:      {"-=", symClassOperator},     //   4: '-='
+		SymMinusEqual:         {"-=", symClassOperator, posInfix},     //   4: '-='
-		SymDoubleMinus:     {"--", symClassOperator},     //   5: '--'
+		SymDoubleMinus:        {"--", symClassOperator, posPostfix},   //   5: '--'
-		SymPlus:            {"+", symClassOperator},      //   6: '+'
+		SymPlus:               {"+", symClassOperator, posInfix},      //   6: '+'
-		SymPlusEqual:       {"+=", symClassOperator},     //   7: '+='
+		SymPlusEqual:          {"+=", symClassOperator, posInfix},     //   7: '+='
-		SymDoublePlus:      {"++", symClassOperator},     //   8: '++'
+		SymDoublePlus:         {"++", symClassOperator, posPostfix},   //   8: '++'
-		SymStar:            {"*", symClassOperator},      //   9: '*'
+		SymStar:               {"*", symClassOperator, posInfix},      //   9: '*'
-		SymDoubleStar:      {"**", symClassOperator},     //  10: '**'
+		SymDoubleStar:         {"**", symClassOperator, posInfix},     //  10: '**'
-		SymSlash:           {"/", symClassOperator},      //  11: '/'
+		SymSlash:              {"/", symClassOperator, posInfix},      //  11: '/'
-		SymBackSlash:       {"\\", symClassOperator},     //  12: '\'
+		SymBackSlash:          {"\\", symClassOperator, posLeaf},      //  12: '\'
-		SymVertBar:         {"|", symClassOperator},      //  13: '|'
+		SymVertBar:            {"|", symClassOperator, posInfix},      //  13: '|'
-		SymDoubleVertBar:   {"||", symClassOperator},     //  14: '||'
+		SymDoubleVertBar:      {"||", symClassOperator, posInfix},     //  14: '||'
-		SymComma:           {",", symClassOperator},      //  15: ','
+		SymComma:              {",", symClassOperator, posInfix},      //  15: ','
-		SymColon:           {":", symClassOperator},      //  16: ':'
+		SymColon:              {":", symClassOperator, posInfix},      //  16: ':'
-		SymSemiColon:       {";", symClassOperator},      //  17: ';'
+		SymSemiColon:          {";", symClassOperator, posInfix},      //  17: ';'
-		SymDot:             {".", symClassOperator},      //  18: '.'
+		SymDot:                {".", symClassOperator, posInfix},      //  18: '.'
-		SymDotSlash:        {"./", symClassOperator},     //  19: './'
+		SymDotSlash:           {"./", symClassOperator, posInfix},     //  19: './'
-		SymQuote:           {"'", symClassDelimiter},     //  20: '\''
+		SymQuote:              {"'", symClassDelimiter, posLeaf},      //  20: '\''
-		SymDoubleQuote:     {"\"", symClassDelimiter},    //  21: '"'
+		SymDoubleQuote:        {"\"", symClassDelimiter, posLeaf},     //  21: '"'
-		SymBackTick:        {"`", symClassOperator},      //  22: '`'
+		SymBackTick:           {"`", symClassDelimiter, posLeaf},      //  22: '`'
-		SymExclamation:     {"!", symClassPostOp},        //  23: '!'
+		SymExclamation:        {"!", symClassOperator, posPostfix},    //  23: '!'
-		SymQuestion:        {"?", symClassOperator},      //  24: '?'
+		SymQuestion:           {"?", symClassOperator, posInfix},      //  24: '?'
-		SymAmpersand:       {"&", symClassOperator},      //  25: '&'
+		SymAmpersand:          {"&", symClassOperator, posInfix},      //  25: '&'
-		SymDoubleAmpersand: {"&&", symClassOperator},     //  26: '&&'
+		SymDoubleAmpersand:    {"&&", symClassOperator, posInfix},     //  26: '&&'
-		SymPercent:         {"%", symClassOperator},      //  27: '%'
+		SymPercent:            {"%", symClassOperator, posInfix},      //  27: '%'
-		SymAt:              {"@", symClassOperator},      //  28: '@'
+		SymAt:                 {"@", symClassOperator, posPrefix},     //  28: '@'
-		SymUndescore:       {"_", symClassOperator},      //  29: '_'
+		SymUndescore:          {"_", symClassIdentifier, posLeaf},     //  29: '_'
-		SymEqual:           {"=", symClassOperator},      //  30: '='
+		SymEqual:              {"=", symClassOperator, posInfix},      //  30: '='
-		SymDoubleEqual:     {"==", symClassOperator},     //  31: '=='
+		SymDoubleEqual:        {"==", symClassOperator, posInfix},     //  31: '=='
-		SymLess:            {"<", symClassOperator},      //  32: '<'
+		SymLess:               {"<", symClassOperator, posInfix},      //  32: '<'
-		SymLessOrEqual:     {"<=", symClassOperator},     //  33: '<='
+		SymLessOrEqual:        {"<=", symClassOperator, posInfix},     //  33: '<='
-		SymGreater:         {">", symClassOperator},      //  34: '>'
+		SymGreater:            {">", symClassOperator, posInfix},      //  34: '>'
-		SymGreaterOrEqual:  {">=", symClassOperator},     //  35: '>='
+		SymGreaterOrEqual:     {">=", symClassOperator, posInfix},     //  35: '>='
-		SymLessGreater:     {"<>", symClassOperator},     //  36: '<>'
+		SymLessGreater:        {"<>", symClassOperator, posInfix},     //  36: '<>'
-		SymNotEqual:        {"!=", symClassOperator},     //  37: '!='
+		SymNotEqual:           {"!=", symClassOperator, posInfix},     //  37: '!='
-		SymDollar:          {"$", symClassOperator},      //  38: '$'
+		SymDollar:             {"$", symClassOperator, posPrefix},     //  38: '$'
-		SymHash:            {"#", symClassOperator},      //  39: '#'
+		SymHash:               {"#", symClassOperator, posPrefix},     //  39: '#'
-		SymOpenRound:       {"(", symClassParenthesis},   //  40: '('
+		SymOpenRound:          {"(", symClassParenthesis, posPrefix},  //  40: '('
-		SymClosedRound:     {")", symClassParenthesis},   //  41: ')'
+		SymClosedRound:        {")", symClassParenthesis, posPostfix}, //  41: ')'
-		SymOpenSquare:      {"[", symClassParenthesis},   //  42: '['
+		SymOpenSquare:         {"[", symClassParenthesis, posPrefix},  //  42: '['
-		SymClosedSquare:    {"]", symClassParenthesis},   //  43: ']'
+		SymClosedSquare:       {"]", symClassParenthesis, posPostfix}, //  43: ']'
-		SymOpenBrace:       {"{", symClassParenthesis},   //  44: '{'
+		SymOpenBrace:          {"{", symClassParenthesis, posPrefix},  //  44: '{'
-		SymClosedBrace:     {"}", symClassParenthesis},   //  45: '}'
+		SymClosedBrace:        {"}", symClassParenthesis, posPostfix}, //  45: '}'
-		SymTilde:           {"~", symClassOperator},      //  46: '~'
+		SymTilde:              {"~", symClassOperator, posPrefix},     //  46: '~'
-		SymDoubleQuestion:  {"??", symClassOperator},     //  47: '??'
+		SymDoubleQuestion:     {"??", symClassOperator, posInfix},     //  47: '??'
-		SymQuestionEqual:   {"?=", symClassOperator},     //  48: '?='
+		SymQuestionEqual:      {"?=", symClassOperator, posInfix},     //  48: '?='
-		SymQuestionExclam:  {"?!", symClassOperator},     //  49: '?!'
+		SymQuestionExclam:     {"?!", symClassOperator, posInfix},     //  49: '?!'
-		SymDoubleAt:        {"@@", symClassOperator},     //  50: '@@'
+		SymDoubleAt:           {"@@", symClassCommand, posLeaf},       //  50: '@@'
-		SymDoubleColon:     {"::", symClassOperator},     //  51: '::'
+		SymDoubleColon:        {"::", symClassOperator, posInfix},     //  51: '::'
-		SymInsert:          {">>", symClassOperator},     //  52: '>>'
+		SymDoubleGreater:      {">>", symClassOperator, posInfix},     //  52: '>>'
-		SymAppend:          {"<<", symClassOperator},     //  53: '<<'
+		SymDoubleLess:         {"<<", symClassOperator, posInfix},     //  53: '<<'
-		SymCaret:           {"^", symClassOperator},      //  54: '^'
+		SymCaret:              {"^", symClassOperator, posInfix},      //  54: '^'
-		SymDollarRound:     {"$(", symClassOperator},     //  55: '$('
+		SymDollarRound:        {"$(", symClassOperator, posPrefix},    //  55: '$('
-		SymOpenClosedRound: {"()", symClassPostOp},       //  56: '()'
+		SymOpenClosedRound:    {"()", symClassOperator, posPostfix},   //  56: '()'
-		SymDoubleDollar:    {"$$", symClassOperator},     //  57: '$$'
+		SymDoubleDollar:       {"$$", symClassCommand, posLeaf},       //  57: '$$'
-		SymDoubleDot:       {"..", symClassOperator},     //  58: '..'
+		SymDoubleDot:          {"..", symClassOperator, posInfix},     //  58: '..'
-		SymTripleDot:       {"...", symClassOperator},    //  59: '...'
+		SymTripleDot:          {"...", symClassOperator, posPostfix},  //  59: '...'
-		SymStarEqual:       {"*=", symClassOperator},     //  60: '*='
+		SymStarEqual:          {"*=", symClassOperator, posInfix},     //  60: '*='
-		SymSlashEqual:      {"/=", symClassOperator},     //  61: '/='
+		SymSlashEqual:         {"/=", symClassOperator, posInfix},     //  61: '/='
-		SymPercEqual:       {"%=", symClassOperator},     //  62: '%='
+		SymPercEqual:          {"%=", symClassOperator, posInfix},     //  62: '%='
+		SymDoubleLessEqual:    {"<<=", symClassOperator, posInfix},    //  63: '<<='
+		SymDoubleGreaterEqual: {">>=", symClassOperator, posInfix},    //  64: '>>='
+		SymAmpersandEqual:     {"&=", symClassOperator, posInfix},     //  65: '&='
+		SymVertBarEqual:       {"|=", symClassOperator, posInfix},     //  65: '|='
+		SymCaretEqual:         {"^=", symClassOperator, posInfix},     //  66: '^='
+		SymPlusGreater:        {"+>", symClassOperator, posInfix},     //  67: '+>'
+		SymLessPlus:           {"<+", symClassOperator, posInfix},     //  68: '<+'
+		SymPreInc:             {"++", symClassOperator, posPrefix},    //    : '++'
+		SymPreDec:             {"--", symClassOperator, posPrefix},    //    : '--'
 		// SymChangeSign
 		// SymUnchangeSign
 		// SymIdentifier
@@ -121,17 +131,17 @@ func init() {
 		// // SymClosedComment                     //   0: '*/'
 		// // SymOneLineComment                    //   0: '//'
 		// keywordBase
-		SymKwAnd:     {"and", symClassOperator},
+		SymKwAnd:     {"and", symClassOperator, posInfix},
-		SymKwNot:     {"not", symClassOperator},
+		SymKwNot:     {"not", symClassOperator, posInfix},
-		SymKwOr:      {"or", symClassOperator},
+		SymKwOr:      {"or", symClassOperator, posInfix},
-		SymKwBut:     {"but", symClassOperator},
+		SymKwBut:     {"but", symClassOperator, posInfix},
-		SymKwFunc:    {"func(", symClassDeclaration},
+		SymKwFunc:    {"func(", symClassDeclaration, posPrefix},
-		SymKwBuiltin: {"builtin", symClassOperator},
+		SymKwBuiltin: {"builtin", symClassOperator, posPrefix},
-		SymKwPlugin:  {"plugin", symClassOperator},
+		SymKwPlugin:  {"plugin", symClassOperator, posPrefix},
-		SymKwIn:      {"in", symClassOperator},
+		SymKwIn:      {"in", symClassOperator, posInfix},
-		SymKwInclude: {"include", symClassOperator},
+		SymKwInclude: {"include", symClassOperator, posPrefix},
-		SymKwNil:     {"nil", symClassValue},
+		SymKwNil:     {"nil", symClassValue, posLeaf},
-		SymKwUnset:   {"unset", symClassOperator},
+		SymKwUnset:   {"unset", symClassOperator, posPrefix},
 	}
 }
 
@@ -169,12 +179,19 @@ func StringEndsWithOperator(s string) bool {
 }
 
 func endingOperator(s string) (sym Symbol) {
+	var matchLength = 0
 	sym = SymNone
-	lower := strings.ToLower(s)
+	lower := strings.TrimRight(strings.ToLower(s), " \t")
 	for symbol, spec := range symbolMap {
-		if spec.kind == symClassOperator && strings.HasSuffix(lower, spec.repr) {
+		if strings.HasSuffix(lower, spec.repr) {
+			if len(spec.repr) > matchLength {
+				matchLength = len(spec.repr)
+				if spec.kind == symClassOperator && (spec.opType == posInfix || spec.opType == posPrefix) {
 					sym = symbol
-			break
+				} else {
+					sym = SymNone
+				}
+			}
 		}
 	}
 	return

symbol.go

@@ -60,8 +60,8 @@ const (
 	SymQuestionExclam                       //  49: '?!'
 	SymDoubleAt                             //  50: '@@'
 	SymDoubleColon                          //  51: '::'
-	SymInsert                            //  52: '>>'
+	SymDoubleGreater                        //  52: '>>'
-	SymAppend                            //  53: '<<'
+	SymDoubleLess                           //  53: '<<'
 	SymCaret                                //  54: '^'
 	SymDollarRound                          //  55: '$('
 	SymOpenClosedRound                      //  56: '()'
@@ -71,8 +71,18 @@ const (
 	SymStarEqual                            //  60: '*='
 	SymSlashEqual                           //  61: '/='
 	SymPercEqual                            //  62: '%='
+	SymDoubleLessEqual                      //  63: '<<='
+	SymDoubleGreaterEqual                   //  64: '>>='
+	SymAmpersandEqual                       //  65: '&='
+	SymVertBarEqual                         //  65: '|='
+	SymCaretEqual                           //  66: '^='
+	SymPlusGreater                          //  67: '+>'
+	SymLessPlus                             //  68: '<+'
 	SymChangeSign
 	SymUnchangeSign
+	SymDereference
+	SymPreInc
+	SymPreDec
 	SymIdentifier
 	SymBool
 	SymInteger

t_bool_test.go

@@ -26,12 +26,13 @@ func TestBool(t *testing.T) {
 		/*  12 */ {`true or false`, true, nil},
 		/*  13 */ {`true or []`, true, nil},
 		/*  14 */ {`[] or false`, nil, errors.New(`got list as left operand type of 'OR' operator, it must be bool`)},
+		/*  15 */ {`!true`, false, nil},
 		/*  13 */ //{`true or []`, nil, errors.New(`[1:8] left operand 'true' [bool] and right operand '[]' [list] are not compatible with operator "OR"`)},
 	}
 
 	// t.Setenv("EXPR_PATH", ".")
 
-	// runTestSuiteSpec(t, section, inputs, 1)
+	// runTestSuiteSpec(t, section, inputs, 15)
 	runTestSuite(t, section, inputs)
 }
 

t_expr_test.go

@@ -29,7 +29,9 @@ func TestExpr(t *testing.T) {
 		/*  15 */ {`a=3; a*=2)+1; a`, nil, `[1:11] unexpected token ")"`},
 		/*  16 */ {`v=[2]; a=1; v[a-=1]=5; v[0]`, int64(5), nil},
 		/*  17 */ {`true ? {"a"} :: {"b"}`, "a", nil},
-		/*  18 */ {`
+		/*  18 */ {`$$`, NewDict(map[any]any{"variables": NewDict(nil), "functions": NewDict(nil)}), nil},
+		///*  19 */ {`$$global`, NewDict(map[any]any{"variables": NewDict(nil), "functions": NewDict(nil)}), nil},
+		/*  19 */ {`
 		ds={
 			"init":func(@end){@current=0 but true},
 			//"current":func(){current},
@@ -44,6 +46,6 @@ func TestExpr(t *testing.T) {
 	}
 	// t.Setenv("EXPR_PATH", ".")
 
-	// runTestSuiteSpec(t, section, inputs, 6, 7, 8, 9)
+	// runTestSuiteSpec(t, section, inputs, 18)
 	runTestSuite(t, section, inputs)
 }

t_fractions_test.go

@@ -25,7 +25,7 @@ func TestFractionsParser(t *testing.T) {
 		/*  12 */ {`builtin "math.arith"; add(1:2, 1.0, 2)`, float64(3.5), nil},
 		/*  13 */ {`builtin "math.arith"; mul(1:2, 2:3)`, newFraction(2, 6), nil},
 		/*  14 */ {`builtin "math.arith"; mul(1:2, 1.0, 2)`, float64(1.0), nil},
-		/*  15 */ {`1:0`, nil, `division by zero`},
+		/*  15 */ {`1:0`, nil, `[1:3] division by zero`},
 		/*  16 */ {`fract(-0.5)`, newFraction(-1, 2), nil},
 		/*  17 */ {`fract("")`, (*FractionType)(nil), `bad syntax`},
 		/*  18 */ {`fract("-1")`, newFraction(-1, 1), nil},
@@ -34,7 +34,7 @@ func TestFractionsParser(t *testing.T) {
 		/*  21 */ {`fract(1,0)`, nil, `fract(): division by zero`},
 		/*  22 */ {`string(1:2)`, "1:2", nil},
 		/*  23 */ {`1+1:2+0.5`, float64(2), nil},
-		/*  24 */ {`1:(2-2)`, nil, `division by zero`},
+		/*  24 */ {`1:(2-2)`, nil, `[1:3] division by zero`},
 		/*  25 */ {`[0,1][1-1]:1`, newFraction(0, 1), nil},
 	}
 	// runTestSuiteSpec(t, section, inputs, 25)

t_iterator_test.go

@@ -9,10 +9,10 @@ import "testing"
 func TestIteratorParser(t *testing.T) {
 	section := "Iterator"
 	inputs := []inputType{
-		/*   1 */ {`include "test-resources/iterator.expr"; it=$(ds,3); ^it`, int64(0), nil},
+		/*   1 */ {`include "test-resources/iterator.expr"; it=$(ds,3); *it`, int64(0), nil},
 		/*   2 */ {`include "test-resources/iterator.expr"; it=$(ds,3); it++; it++`, int64(1), nil},
 		/*   3 */ {`include "test-resources/iterator.expr"; it=$(ds,3); it++; it++; #it`, int64(3), nil},
-		/*   4 */ {`include "test-resources/iterator.expr"; it=$(ds,3); it++; it++; it.reset; ^it`, int64(0), nil},
+		/*   4 */ {`include "test-resources/iterator.expr"; it=$(ds,3); it++; it++; it.reset; *it`, int64(0), nil},
 		/*   5 */ {`builtin "math.arith"; include "test-resources/iterator.expr"; it=$(ds,3); add(it)`, int64(6), nil},
 		/*   6 */ {`builtin "math.arith"; include "test-resources/iterator.expr"; it=$(ds,3); mul(it)`, int64(0), nil},
 		/*   7 */ {`builtin "math.arith"; include "test-resources/file-reader.expr"; it=$(ds,"test-resources/int.list"); mul(it)`, int64(12000), nil},

t_list_test.go

@@ -23,8 +23,8 @@ func TestListParser(t *testing.T) {
 		/*   9 */ {`mul([1,4,3.0,2])`, float64(24.0), nil},
 		/*  10 */ {`add([1,"hello"])`, nil, `add(): param nr 2 (2 in 1) has wrong type string, number expected`},
 		/*  11 */ {`[a=1,b=2,c=3] but a+b+c`, int64(6), nil},
-		/*  12 */ {`[1,2,3] << 2+2`, newListA(int64(1), int64(2), int64(3), int64(4)), nil},
+		/*  12 */ {`[1,2,3] <+ 2+2`, newListA(int64(1), int64(2), int64(3), int64(4)), nil},
-		/*  13 */ {`2-1 >> [2,3]`, newListA(int64(1), int64(2), int64(3)), nil},
+		/*  13 */ {`2-1 +> [2,3]`, newListA(int64(1), int64(2), int64(3)), nil},
 		/*  14 */ {`[1,2,3][1]`, int64(2), nil},
 		/*  15 */ {`ls=[1,2,3] but ls[1]`, int64(2), nil},
 		/*  16 */ {`ls=[1,2,3] but ls[-1]`, int64(3), nil},
@@ -33,25 +33,25 @@ func TestListParser(t *testing.T) {
 		/*  19 */ {`["a", "b", "c"]`, newList([]any{"a", "b", "c"}), nil},
 		/*  20 */ {`#["a", "b", "c"]`, int64(3), nil},
 		/*  21 */ {`"b" in ["a", "b", "c"]`, true, nil},
-		/*  22 */ {`a=[1,2]; (a)<<3`, newListA(int64(1), int64(2), int64(3)), nil},
+		/*  22 */ {`a=[1,2]; (a)<+3`, newListA(int64(1), int64(2), int64(3)), nil},
-		/*  23 */ {`a=[1,2]; (a)<<3; a`, newListA(int64(1), int64(2)), nil},
+		/*  23 */ {`a=[1,2]; (a)<+3; a`, newListA(int64(1), int64(2)), nil},
 		/*  24 */ {`["a","b","c","d"][1]`, "b", nil},
 		/*  25 */ {`["a","b","c","d"][1,1]`, nil, `[1:19] one index only is allowed`},
 		/*  26 */ {`[0,1,2,3,4][:]`, newListA(int64(0), int64(1), int64(2), int64(3), int64(4)), nil},
-		/*  27 */ {`["a", "b", "c"] << ;`, nil, `[1:18] infix operator "<<" requires two non-nil operands, got 1`},
+		/*  27 */ {`["a", "b", "c"] <+ ;`, nil, `[1:18] infix operator "<+" requires two non-nil operands, got 1`},
 		/*  28 */ {`2 << 3;`, int64(16), nil},
-		/*  29 */ {`but >> ["a", "b", "c"]`, nil, `[1:6] infix operator ">>" requires two non-nil operands, got 0`},
+		/*  29 */ {`but +> ["a", "b", "c"]`, nil, `[1:6] infix operator "+>" requires two non-nil operands, got 0`},
 		/*  30 */ {`2 >> 3;`, int64(0), nil},
-		/*  31 */ {`a=[1,2]; a<<3`, newListA(int64(1), int64(2), int64(3)), nil},
+		/*  31 */ {`a=[1,2]; a<+3`, newListA(int64(1), int64(2), int64(3)), nil},
-		/*  33 */ {`a=[1,2]; 5>>a`, newListA(int64(5), int64(1), int64(2)), nil},
+		/*  32 */ {`a=[1,2]; 5+>a`, newListA(int64(5), int64(1), int64(2)), nil},
-		/*  34 */ {`L=[1,2]; L[0]=9; L`, newListA(int64(9), int64(2)), nil},
+		/*  33 */ {`L=[1,2]; L[0]=9; L`, newListA(int64(9), int64(2)), nil},
-		/*  35 */ {`L=[1,2]; L[5]=9; L`, nil, `index 5 out of bounds (0, 1)`},
+		/*  34 */ {`L=[1,2]; L[5]=9; L`, nil, `index 5 out of bounds (0, 1)`},
-		/*  36 */ {`L=[1,2]; L[]=9; L`, nil, `[1:12] index/key specification expected, got [] [list]`},
+		/*  35 */ {`L=[1,2]; L[]=9; L`, nil, `[1:12] index/key specification expected, got [] [list]`},
-		/*  37 */ {`L=[1,2]; L[nil]=9;`, nil, `[1:12] index/key is nil`},
+		/*  36 */ {`L=[1,2]; L[nil]=9;`, nil, `[1:12] index/key is nil`},
-		/*  38 */ {`[0,1,2,3,4][2:3]`, newListA(int64(2)), nil},
+		/*  37 */ {`[0,1,2,3,4][2:3]`, newListA(int64(2)), nil},
-		/*  39 */ {`[0,1,2,3,4][3:-1]`, newListA(int64(3)), nil},
+		/*  38 */ {`[0,1,2,3,4][3:-1]`, newListA(int64(3)), nil},
-		/*  40 */ {`[0,1,2,3,4][-3:-1]`, newListA(int64(2), int64(3)), nil},
+		/*  30 */ {`[0,1,2,3,4][-3:-1]`, newListA(int64(2), int64(3)), nil},
-		/*  41 */ {`[0,1,2,3,4][0:]`, newListA(int64(0), int64(1), int64(2), int64(3), int64(4)), nil},
+		/*  40 */ {`[0,1,2,3,4][0:]`, newListA(int64(0), int64(1), int64(2), int64(3), int64(4)), nil},
 	}
 
 	// t.Setenv("EXPR_PATH", ".")

t_operator_test.go

@@ -14,10 +14,29 @@ func TestOperator(t *testing.T) {
 		/*   1 */ {`a=1; unset "a"; a`, nil, `undefined variable or function "a"`},
 		/*   2 */ {`a=1; unset ["a", "b"]`, int64(1), nil},
 		/*   3 */ {`f=func(){3}; unset "f()"`, int64(1), nil},
+		/*   4 */ {`a=1; a<<=1+0`, int64(2), nil},
+		/*   5 */ {`a=2; a>>=1+0`, int64(1), nil},
+		/*   6 */ {`1<<1`, int64(2), nil},
+		/*   7 */ {`1>>1`, int64(0), nil},
+		/*   8 */ {`1|2`, int64(3), nil},
+		/*   9 */ {`a=1; a|=2`, int64(3), nil},
+		/*  10 */ {`3&1`, int64(1), nil},
+		/*  11 */ {`a=3; a&=1`, int64(1), nil},
+		/*  12 */ {`~1`, int64(-2), nil},
+		/*  13 */ {`0x10`, int64(16), nil},
+		/*  14 */ {`0x1X`, nil, `[1:5] two adjacent operators: "1" and "X"`},
+		/*  15 */ {`0o10`, int64(8), nil},
+		/*  16 */ {`0b10`, int64(2), nil},
+		/*  17 */ {`~true`, nil, `[1:2] prefix/postfix operator "~" do not support operand 'true' [bool]`},
+		/*  18 */ {`1^2`, int64(3), nil},
+		/*  19 */ {`3^2`, int64(1), nil},
+		/*  19 */ {`a=1; a^=2`, int64(3), nil},
+		/*  20 */ {`a=1; ++a`, int64(2), nil},
+		/*  21 */ {`a=1; --a`, int64(0), nil},
 	}
 
 	// t.Setenv("EXPR_PATH", ".")
 
-	//runTestSuiteSpec(t, section, inputs, 3)
+	// runTestSuiteSpec(t, section, inputs, 4)
 	runTestSuite(t, section, inputs)
 }

t_parser_test.go

@@ -78,8 +78,8 @@ func TestGeneralParser(t *testing.T) {
 		/*  64 */ {`"1.5" != `, nil, `[1:8] infix operator "!=" requires two non-nil operands, got 1`},
 		/*  65 */ {"+1.5", float64(1.5), nil},
 		/*  66 */ {"+", nil, `[1:2] prefix operator "+" requires one non-nil operand`},
-		/*  67 */ {"4 / 0", nil, `division by zero`},
+		/*  67 */ {"4 / 0", nil, `[1:4] division by zero`},
-		/*  68 */ {"4.0 / 0", nil, `division by zero`},
+		/*  68 */ {"4.0 / 0", nil, `[1:6] division by zero`},
 		/*  69 */ {"4.0 / \n2", float64(2.0), nil},
 		/*  70 */ {`123`, int64(123), nil},
 		/*  71 */ {`1.`, float64(1.0), nil},
@@ -142,6 +142,6 @@ func TestGeneralParser(t *testing.T) {
 	}
 
 	// t.Setenv("EXPR_PATH", ".")
-	//runTestSuiteSpec(t, section, inputs, 130)
+	// runTestSuiteSpec(t, section, inputs, 114)
 	runTestSuite(t, section, inputs)
 }

t_strings_test.go

@@ -9,6 +9,7 @@ import (
 )
 
 func TestStringsParser(t *testing.T) {
+	section := "String"
 	inputs := []inputType{
 		/*  1 */ {`"uno" + "due"`, `unodue`, nil},
 		/*  2 */ {`"uno" + 2`, `uno2`, nil},
@@ -16,6 +17,12 @@ func TestStringsParser(t *testing.T) {
 		/*  4 */ {`"uno" * (2+1)`, `unounouno`, nil},
 		/*  5 */ {`"abc"[1]`, `b`, nil},
 		/*  6 */ {`#"abc"`, int64(3), nil},
+		/*  7 */ {`"192.168.0.240" / "."`, newListA("192", "168", "0", "240"), nil},
+		/*  8 */ {`("192.168.0.240" / ".")[1]`, "168", nil},
+		/*  9 */ {`"AF3B0Dz" / 2`, newListA("AF", "3B", "0D", "z"), nil},
+		/* 10 */ {`"AF3B0Dz" / 0`, nil, "[1:12] division by zero"},
 	}
-	runTestSuite(t, "String", inputs)
+
+	// runTestSuiteSpec(t, section, inputs, 8)
+	runTestSuite(t, section, inputs)
 }

term.go

@@ -15,21 +15,26 @@ const (
 	priRange
 	priBut
 	priAssign
+	priInsert
 	priOr
 	priAnd
 	priNot
 	priRelational
-	priBinary
+	priBitwiseOr
+	priBitwiseAnd
+	priBitwiseNot
 	priSum
 	priProduct
 	priFraction
 	priSelector
+	priBinShift
 	priSign
 	priFact
 	priIterValue
 	priDefault
 	priIncDec
 	priDot
+	priDereference
 	priValue
 )
 
@@ -199,6 +204,10 @@ func (term *term) errIncompatibleType(value any) error {
 		term.source(), value, TypeName(value))
 }
 
+func (term *term) errDivisionByZero() error {
+	return term.tk.Errorf("division by zero")
+}
+
 func (term *term) Errorf(template string, args ...any) (err error) {
 	err = term.tk.Errorf(template, args...)
 	return

token.go

@@ -79,6 +79,10 @@ func (tk *Token) IsSymbol(sym Symbol) bool {
 	return tk.Sym == sym
 }
 
+func (tk *Token) SetSymbol(sym Symbol) {
+	tk.Sym = sym
+}
+
 func (tk *Token) Errorf(template string, args ...any) (err error) {
 	err = fmt.Errorf(fmt.Sprintf("[%d:%d] ", tk.row, tk.col)+template, args...)
 	return