README.adoc: examples, relational operators table completed

README.adoc

@@ -25,6 +25,32 @@ toc::[]
 == Expr
 _Expr_ is a GO package capable of analysing, interpreting and calculating expressions.
 
+.Examples taken from parser_test.go
+[source,go]
+----
+`1.0 / 2`                      // 0.5
+`435 + 105 * 2 - 1`            // 644
+`4 == (3-1)*(10/5)`            // true
+`"uno" * (2+1)`                // `unounouno`
+`2+3 but 5*2`                  // 10 <1>
+`add(add(1+4),3+2,5*(3-2))`    // 15 <2>
+`a=5; b=2; add(a, b*3)`        // 11 <3>
+`two=func(){2}; two()`         // 2  <4>
+`double=func(x){2*x}; a=4+1; two=func() {2}; (double(3+a) + 1) * two()`  // 34
+`import("./test-funcs.expr"); (double(3+a) + 1) * two()`  // 34 <5>
+`[1,2,"hello"]`                // Mixed types list
+`[1,2]+[3]`                    // append list, result: [1,2,3]
+`add([1,[2,2],3,2])`           // Deep list sum, result: 10 <2>
+`[a=1,b=2,c=3] but a+b+c`      // 6
+----
+
+<1> [blue]`but` operator.
+<2> The _add()_ function definition may be changed in the future.
+<3> Multiple expression. Only the last expression value will returned.
+<4> Simple function definition: _two()_ returns 2.
+<5> _import()_ function imports expressions from the specified files. See file _test-funcs.expr_.
+
+
 === Usage
 
 
@@ -82,7 +108,7 @@ func main() {
 ----
 
 === Data types
-_Expr_ supports numerical, string, relational, and boolean expressions.
+_Expr_ supports numerical, string, relational, boolean expressions, and mixed-type lists.
 
 ==== Numbers
 Numbers can be integers (GO int64) and float (GO float64). In mixed operations involving integers and floats, integers are automatically promoted to floats.
@@ -92,24 +118,27 @@ Numbers can be integers (GO int64) and float (GO float64). In mixed operations i
 |===
 | Symbol    | Operation     | Description               | Examples
 
-| `+` / `-` | _change sign_ | Change the sign of values | `-1` _[-1]_, `-(+2)` _[-2]_
+| [blue]`+` / [blue]`-` | _change sign_ | Change the sign of values | [blue]`-1` _[-1]_, [blue]`-(+2)` _[-2]_
 
-| `+` | _sum_ | Add two values | `-1 + 2` _[1]_, `4 + 0.5` _[4.5]_
+| [blue]`+` | _sum_ | Add two values | [blue]`-1 + 2` _[1]_, [blue]`4 + 0.5` _[4.5]_
 
-| `-` | _subtracion_ | Subtract the right value from the left one | `3 - 1` _[2]_, `4 - 0.5` _[3.5]_
+| [blue]`-` | _subtracion_ | Subtract the right value from the left one | [blue]`3 - 1` _[2]_, [blue]`4 - 0.5` _[3.5]_
 
-| `*` | _product_ | Multiply two values | `-1 * 2` _[-2]_, `4 * 0.5` _[2.0]_
+| [blue]`*` | _product_ | Multiply two values | `-1 * 2` _[-2]_, [blue]`4 * 0.5` _[2.0]_
 
-| `/` | _Division_ | Divide the left value by the right one | `-1 / 2` _[0]_, `1.0 / 2` _[0.5]_
+| [blue]`/` | _Division_ | Divide the left value by the right one | [blue]`-1 / 2` _[0]_, [blue]`1.0 / 2` _[0.5]_
 
-| `./` | _Float division_ | Force float division | `-1 ./ 2` _[-0.5]_
+| [blue]`./` | _Float division_ | Force float division | [blue]`-1 ./ 2` _[-0.5]_
 
-| `%` | _Modulo_ | Remainder of the integer division | `5 % 2` _[1]_
+| [blue]`%` | _Modulo_ | Remainder of the integer division | [blue]`5 % 2` _[1]_
 
 |=== 
 
 ==== String
-Strings are character sequences enclosed between two double quote `"`.
+Strings are character sequences enclosed between two double quote [blue]`"`. Example: [blue]`"I'm a string"`.
+
+Some arithmetic operators can also be used with strings.
+
 
 ==== Boolean
 Boolean data type has two values only: _true_ and _false_. Relational and Boolean expressions produce a Boolean values.
@@ -120,19 +149,23 @@ Boolean data type has two values only: _true_ and _false_. Relational and Boolea
 |===
 | Symbol    | Operation     | Description               | Examples
 
-| `<` | _Less_ | True if the left value is less than the right one | `5 < 2` _[false]_, `"a" < "b"` [true]
+| [blue]`==` | _Equal_ | True if the left value is equal to the right one | [blue]`5 == 2` _[false]_, [blue]`"a" == "a"` [true]
-| `\<=` | _Less or Greater_ | True if the left value is less or greater than the right one | `5 <= 2` _[false]_, `"b" <= "b"` [true]
+| [blue]`!=` | _Not Equal_ | True if the left value is NOT equal to the right one | [blue]`5 != 2` _[true]_, [blue]`"a" != "a"` [false]
+| [blue]`<` | _Less_ | True if the left value is less than the right one | [blue]`5 < 2` _[false]_, [blue]`"a" < "b"` [true]
+| [blue]`\<=` | _Less or Equal_ | True if the left value is less than or equal to the right one | [blue]`5 \<= 2` _[false]_, [blue]`"b" \<= "b"` [true]
+| [blue]`>` | _Greater_ | True if the left value is greater than the right one | [blue]`5 > 2` _[true]_, [blue]`"a" < "b"` [false]
+| [blue]`>=` | _Greater or Equal_ | True if the left value is greater than or equal to the right one | [blue]`5 >= 2` _[true]_, [blue]`"b" \<= "b"` [true]
 |===
 
 
 .Boolean operators
-[cols="^1,^2,6,4"]
+[cols="^2,^2,6,4"]
 |===
 | Symbol    | Operation     | Description               | Examples
 
-| `NOT` | _Not_ | True if the right value is false | `NOT true` _[false]_, `NOT (2 < 1)` _[true]_
+| [blue]`NOT` | _Not_ | True if the right value is false | [blue]`NOT true` _[false]_, [blue]`NOT (2 < 1)` _[true]_
 
-| `AND` / `&&` | _And_ | True if both left and right values are true  | `false && true` _[false]_, `"a" < "b" AND NOT (2 < 1)` _[true]_
+| [blue]`AND` / [blue]`&&` | _And_ | True if both left and right values are true  | [blue]`false && true` _[false]_, [blue]`"a" < "b" AND NOT (2 < 1)` _[true]_
 
-| `OR` / `\|\|` | _Or_ | True if at least one of the left and right values integers true| `false or true` _[true]_, `"a" == "b" OR (2 == 1)` _[false]_
+| [blue]`OR` / [blue]`\|\|` | _Or_ | True if at least one of the left and right values integers true| [blue]`false or true` _[true]_, [blue]`"a" == "b" OR (2 == 1)` _[false]_
 |===