go-pkg/expr
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Doc: little changes

Browse Source
This commit is contained in:
Celestino Amoroso
2024-06-21 09:06:25 +02:00
parent a1a62b6794
commit 3b641ac793
2 changed files with 173 additions and 57 deletions
Download Patch File Download Diff File Expand all files Collapse all files
doc/Expr.html
+111 -33
View File
@@ -573,8 +573,9 @@ pre.rouge .ss {
<li><a href="#_priorities_of_operators">5. Priorities of operators</a></li>
<li><a href="#_functions">6. Functions</a>
<ul class="sectlevel2">
<li><a href="#_function_calls">6.1. Function calls</a></li>
<li><a href="#_function_definitions">6.2. Function definitions</a></li>
<li><a href="#_expr_function_definition">6.1. <em>Expr</em> function definition</a></li>
<li><a href="#_golang_function_definition">6.2. <em>Golang</em> function definition</a></li>
<li><a href="#_function_calls">6.3. Function calls</a></li>
</ul>
</li>
<li><a href="#_iterators">7. Iterators</a></li>
@@ -593,7 +594,7 @@ pre.rouge .ss {
<div class="sectionbody">
<!-- toc disabled -->
<div class="paragraph">
<p><mark>TODO: Work in progress (last update on 2024/06/17, 16:31 a.m.)</mark></p>
<p><mark>TODO: Work in progress (last update on 2024/06/21, 05:40 a.m.)</mark></p>
</div>
</div>
</div>
@@ -1581,7 +1582,7 @@ The assign operator <code class="blue">=</code> returns the value assigned to th
<code class="green">3</code></p>
</div>
<div class="paragraph">
<p><code>&gt;&gt;&gt;</code> <code class="blue">x = 5.2 * (9-3)</code> <em class="gray">// The assigned value has the approximation error typical of the float data-type</em><br>
<p><code>&gt;&gt;&gt;</code> <code class="blue">x = 5.2 * (9-3)</code> <em class="gray">// The assigned value has the typical approximation error of the float data-type</em><br>
<code class="green">31.200000000000003</code></p>
</div>
<div class="paragraph">
@@ -1606,6 +1607,14 @@ The assign operator <code class="blue">=</code> returns the value assigned to th
<div class="paragraph">
<p>The semicolon operator <code class="blue">;</code> is an infixed pseudo-operator. It evaluates the left expression first and then the right expression. The value of the latter is the final result.</p>
</div>
<div class="exampleblock">
<div class="title">Example 12. Mult-expression syntax</div>
<div class="content">
<div class="paragraph">
<p><strong><em>multi-expression</em></strong> = <em>expression</em> {"<strong>;</strong>" <em>expression</em> }</p>
</div>
</div>
</div>
<div class="paragraph">
<p>An expression that contains <code class="blue">;</code> is called a <em>multi-expression</em> and each component expressione is called a <em>sub-expression</em>.</p>
</div>
@@ -1704,25 +1713,37 @@ Technically <code class="blue">;</code> is not treated as a real operator. It ac
<div class="paragraph">
<div class="title">Examples</div>
<p><code>&gt;&gt;&gt;</code> <code class="blue">1 ? {"a"} : {"b"}</code><br>
<code class="green">b</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">10 ? {"a"} : {"b"} :: {"c"}</code><br>
<code class="green">c'<br>
[green]</code>&gt;&gt;&gt;` <code class="blue">10 ? {"a"} :[true, 2+8] {"b"} :: {"c"}</code><br>
<code class="green">b</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">10 ? {"a"} :[true, 2+8] {"b"} ::[10] {"c"}</code><br>
<code class="red">Parse Error: [1:34] case list in default clause</code><br>
<code class="green">&gt;&gt;&gt;</code> <code class="blue">10 ? {"a"} :[10] {x="b" but x} :: {"c"}</code><br>
<code class="green">b</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">10 ? {"a"} :[10] {x="b"; x} :: {"c"}</code><br>
<code class="green">b</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">10 ? {"a"} : {"b"}</code><br>
<code class="green">b</code></p>
</div>
<div class="paragraph">
<p><code>&gt;&gt;&gt;</code> <code class="blue">10 ? {"a"} : {"b"} :: {"c"}</code><br>
<code class="green">c</code></p>
</div>
<div class="paragraph">
<p><code>&gt;&gt;&gt;</code> <code class="blue">10 ? {"a"} :[true, 2+8] {"b"} :: {"c"}</code><br>
<code class="green">b</code></p>
</div>
<div class="paragraph">
<p><code>&gt;&gt;&gt;</code> <code class="blue">10 ? {"a"} :[true, 2+8] {"b"} :: [10] {"c"}</code><br>
<code class="red">Parse Error: [1:34] case list in default clause</code></p>
</div>
<div class="paragraph">
<p><code>&gt;&gt;&gt;</code> <code class="blue">10 ? {"a"} :[10] {x="b" but x} :: {"c"}</code><br>
<code class="green">b</code></p>
</div>
<div class="paragraph">
<p><code>&gt;&gt;&gt;</code> <code class="blue">10 ? {"a"} :[10] {x="b"; x} :: {"c"}</code><br>
<code class="green">b</code></p>
</div>
<div class="paragraph">
<p><code>&gt;&gt;&gt;</code> <code class="blue">10 ? {"a"} : {"b"}</code><br>
<code class="red">Eval Error: [1:3] no case catches the value (10) of the selection expression</code></p>
</div>
</div>
<div class="sect2">
<h3 id="_variable_default_value_and"><a class="anchor" href="#_variable_default_value_and"></a><a class="link" href="#_variable_default_value_and">4.5. Variable default value <code class="blue">??</code> and <code class="blue">?=</code></a></h3>
<div class="paragraph">
<p>The left operand of these two operators must be a variable. The right operator can be any expression. They return the value of the variable if this is define; otherwise they return the value of the right expression.</p>
<p>The left operand of these two operators must be a variable. The right operator can be any expression. They return the value of the variable if this is defined; otherwise they return the value of the right expression.</p>
</div>
<div class="admonitionblock important">
<table>
@@ -1731,26 +1752,32 @@ Technically <code class="blue">;</code> is not treated as a real operator. It ac
<i class="fa icon-important" title="Important"></i>
</td>
<td class="content">
If the left variable is defined, the right expression is not evuated at all.
If the left variable is defined, the right expression is not evaluated at all.
</td>
</tr>
</table>
</div>
<div class="paragraph">
<p>The <code class="blue">??</code> do not change the status of the left variable.</p>
<p>The <code class="blue">??</code> operator do not change the status of the left variable.</p>
</div>
<div class="paragraph">
<p>The <code class="blue">?=</code> assigns the calculated value of the right expression to the left variable.</p>
</div>
<div class="paragraph">
<div class="title">Examples</div>
<p><code>&gt;&gt;&gt;</code> <code class="blue">var ?? (1+2)&#8217;
[green]`3</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">var</code><br>
<code class="red">Eval Error: undefined variable or function "var"</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">var ?= (1+2)</code><br>
<code class="green">3</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">var</code><br>
<p><code>&gt;&gt;&gt;</code> <code class="blue">var ?? (1+2)&#8217;<br>
[green]`3</code></p>
</div>
<div class="paragraph">
<p><code>&gt;&gt;&gt;</code> <code class="blue">var</code><br>
<code class="red">Eval Error: undefined variable or function "var"</code></p>
</div>
<div class="paragraph">
<p><code>&gt;&gt;&gt;</code> <code class="blue">var ?= (1+2)</code><br>
<code class="green">3</code></p>
</div>
<div class="paragraph">
<p><code>&gt;&gt;&gt;</code> <code class="blue">var</code>
<code class="green">3</code></p>
</div>
<div class="admonitionblock note">
@@ -1820,6 +1847,26 @@ These operators have a high priority, in particular higher than the operator <co
<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" rowspan="2"><p class="tableblock"><strong>DEFAULT</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>Default value</em></p></td>
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>variable</em> <code>??</code> <em>any-expr</em> &#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>Infix</em></p></td>
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Default/assign value</em></p></td>
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>variable</em> <code>?=</code> <em>any-expr</em> &#8594; <em>any</em></p></td>
</tr>
<tr>
<td class="tableblock halign-center valign-top"><p class="tableblock"><strong>ITER</strong><sup>1</sup></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>Prefix</em></p></td>
<td class="tableblock halign-center valign-top"><p class="tableblock"><em>Iterator value</em></p></td>
<td class="tableblock halign-center valign-top"><p class="tableblock"><code>()</code> <em>iterator</em> &#8594; <em>any</em></p></td>
</tr>
<tr>
<td class="tableblock halign-center valign-top"><p class="tableblock"><strong>FACT</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>
@@ -2050,6 +2097,9 @@ These operators have a high priority, in particular higher than the operator <co
</tr>
</tbody>
</table>
<div class="paragraph">
<p><sup>1</sup> Experimental</p>
</div>
</div>
</div>
<div class="sect1">
@@ -2068,19 +2118,47 @@ These operators have a high priority, in particular higher than the operator <co
</li>
</ul>
</div>
<div class="sect2">
<h3 id="_expr_function_definition"><a class="anchor" href="#_expr_function_definition"></a><a class="link" href="#_expr_function_definition">6.1. <em>Expr</em> function definition</a></h3>
<div class="paragraph">
<p>In <em>Expr</em> functions compute values in a local context (scope) that do not make effects on the calling context. This is the normal behavior. Using the reference operator <code class="blue">@</code> it is possibile to export local definition to the calling context.</p>
<p>A function is identified and referenced by its name. It can have zero or more parameter. <em>Expr</em> functions also support optional parameters.</p>
</div>
<div class="olist arabic">
<ol class="arabic">
<li>
<p>Expr&#8217;s function definition syntax</p>
</li>
</ol>
</div>
<div class="exampleblock">
<div class="content">
<div class="paragraph">
<p><strong><em>function-definition</em></strong> = <em>identifier</em> "<strong>=</strong>" "<strong>func(</strong>" [<em>param-list</em>] "<strong>)</strong>" "<strong>{</strong>" <em>multi-expression</em> "<strong>}</strong>"
<em>param_list</em> = <em>required-param-list</em> [ "<strong>,</strong>" <em>optional-param-list</em> ]
<em>required-param-list</em> = <em>identifier</em> { "<strong>,</strong>" <em>identifier</em> }
<em>optional-param-list</em> = <em>optional-parm</em> { "<strong>,</strong>" <em>optional-param</em> }
<em>optional-param</em> = <em>identifier</em> "<strong>=</strong>" <em>any-expr</em></p>
</div>
</div>
</div>
<div class="paragraph">
<div class="title">Examples</div>
<p><mark>TODO</mark></p>
</div>
</div>
<div class="sect2">
<h3 id="_function_calls"><a class="anchor" href="#_function_calls"></a><a class="link" href="#_function_calls">6.1. Function calls</a></h3>
<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>
</div>
</div>
<div class="sect2">
<h3 id="_function_calls"><a class="anchor" href="#_function_calls"></a><a class="link" href="#_function_calls">6.3. Function calls</a></h3>
<div class="paragraph">
<p><mark>TODO: function calls operations</mark></p>
</div>
</div>
<div class="sect2">
<h3 id="_function_definitions"><a class="anchor" href="#_function_definitions"></a><a class="link" href="#_function_definitions">6.2. Function definitions</a></h3>
<div class="paragraph">
<p><mark>TODO: function definitions operations</mark></p>
<p>Functions compute values in a local context (scope) that do not make effects on the calling context. This is the normal behavior. Using the reference operator <code class="blue">@</code> it is possibile to export local definition to the calling context.</p>
</div>
</div>
</div>
@@ -2122,7 +2200,7 @@ These operators have a high priority, in particular higher than the operator <co
</div>
<div id="footer">
<div id="footer-text">
Last updated 2024-06-20 07:07:23 +0200
Last updated 2024-06-21 09:06:12 +0200
</div>
</div>
</body>