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Doc: some typo and better examples

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Celestino Amoroso
2024-05-11 20:14:54 +02:00
parent 50e7168214
commit 47be0c66cf
2 changed files with 97 additions and 69 deletions
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@@ -868,6 +868,28 @@ pre.rouge .ss {
</tr>
</tbody>
</table>
<div class="paragraph">
<p>The items of strings can be accessed using the dot <code>.</code> operator.</p>
</div>
<div class="listingblock">
<div class="title">Item access syntax</div>
<div class="content">
<pre class="rouge highlight"><code data-lang="bnf">&lt;item&gt; ::= &lt;string-expr&gt;"."&lt;index-expr&gt;</code></pre>
</div>
</div>
<div class="paragraph">
<div class="title">String examples</div>
<p><code>&gt;&gt;&gt;</code> <code class="blue">s="abc"</code> <em class="gray">assign the string to variable s</em><br>
<code class="green">abc</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">s.1</code> <em class="gray">char at position 1 (starting from 0)</em><br>
<code class="green">b</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">s.(-1)</code> <em class="gray">char at position -1, the rightmost one</em><br>
<code class="green">c</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">#s</code> <em class="gray">number of chars</em><br>
<code class="gren">3</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">#"abc"</code> <em class="gray">number of chars</em><br>
<code class="green">3</code><br></p>
</div>
</div>
<div class="sect2">
<h3 id="_boolean"><a class="anchor" href="#_boolean"></a><a class="link" href="#_boolean">2.4. Boolean</a></h3>
@@ -1059,23 +1081,22 @@ pre.rouge .ss {
<pre class="rouge highlight"><code data-lang="bnf">&lt;item&gt; ::= &lt;list-expr&gt;"."&lt;index-expr&gt;</code></pre>
</div>
</div>
<div class="listingblock">
<div class="paragraph">
<div class="title">Items of list</div>
<div class="content">
<pre class="rouge highlight"><code data-lang="go"><span class="s">`&gt;&gt;&gt;`</span> <span class="p">[</span><span class="n">blue</span><span class="p">]</span><span class="s">`[1,2,3].1`</span>
<span class="p">[</span><span class="n">green</span><span class="p">]</span><span class="s">`2`</span>
<span class="s">`&gt;&gt;&gt;`</span> <span class="p">[</span><span class="n">blue</span><span class="p">]</span><span class="s">`list=[1,2,3]; list.1`</span>
<span class="p">[</span><span class="n">green</span><span class="p">]</span><span class="s">`2`</span>
<span class="s">`&gt;&gt;&gt;`</span> <span class="p">[</span><span class="n">blue</span><span class="p">]</span><span class="s">`["one","two","three"].1`</span>
<span class="p">[</span><span class="n">green</span><span class="p">]</span><span class="s">`two`</span>
<span class="s">`&gt;&gt;&gt;`</span> <span class="p">[</span><span class="n">blue</span><span class="p">]</span><span class="s">`list=["one","two","three"]; list.(2-1)`</span>
<span class="p">[</span><span class="n">green</span><span class="p">]</span><span class="s">`two`</span>
<span class="s">`&gt;&gt;&gt;`</span> <span class="p">[</span><span class="n">blue</span><span class="p">]</span><span class="s">`list.(-1)`</span>
<span class="p">[</span><span class="n">green</span><span class="p">]</span><span class="s">`three`</span>
<span class="s">`&gt;&gt;&gt;`</span> <span class="p">[</span><span class="n">blue</span><span class="p">]</span><span class="s">`list.(-1)`</span>
<span class="p">[</span><span class="n">green</span><span class="p">]</span><span class="s">`three`</span>
<span class="s">`&gt;&gt;&gt;`</span> <span class="p">[</span><span class="n">blue</span><span class="p">]</span><span class="s">`list.(10)`</span></code></pre>
</div>
<p><code>&gt;&gt;&gt;</code> <code class="blue">[1,2,3].1</code><br>
<code class="green">2</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">list=[1,2,3]; list.1</code><br>
<code class="green">2</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">["one","two","three"].1</code><br>
<code class="green">two</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">list=["one","two","three"]; list.(2-1)</code><br>
<code class="green">two</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">list.(-1)</code><br>
<code class="green">three</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">list.(10)</code><br>
<code class="red">Eval Error: [1:9] index 10 out of bounds</code><br>
<code>&gt;&gt;&gt;</code> <code class="blue">#list</code><br>
<code class="green">3</code></p>
</div>
</div>
</div>
@@ -1087,7 +1108,7 @@ pre.rouge .ss {
<p>The <em>dictionary</em> data-type is set of pairs <em>key/value</em>. It is also known as <em>map</em> or <em>associative array</em>. Dictionary literals are sequences of pairs separated by comma <code>,</code>; sequences are enclosed between brace brackets.</p>
</div>
<div class="listingblock">
<div class="title">List examples</div>
<div class="title">Dictionary examples</div>
<div class="content">
<pre class="rouge highlight"><code data-lang="go"><span class="p">{</span><span class="m">1</span><span class="o">:</span><span class="s">"one"</span><span class="p">,</span> <span class="m">2</span><span class="o">:</span><span class="s">"two"</span><span class="p">}</span>
<span class="p">{</span><span class="s">"one"</span><span class="o">:</span><span class="m">1</span><span class="p">,</span> <span class="s">"two"</span><span class="o">:</span> <span class="m">2</span><span class="p">}</span>
@@ -1112,7 +1133,7 @@ Support for dictionaries is still ongoing.
<h2 id="_variables"><a class="anchor" href="#_variables"></a><a class="link" href="#_variables">4. Variables</a></h2>
<div class="sectionbody">
<div class="paragraph">
<p>A variable is an identifier with an assigned value. Variables are stored in the object that implements the <em>ExprContext</em> interface.</p>
<p>A variable is an identifier with an assigned value. Variables are stored in the object that implements the Go <em>ExprContext</em> interface, e.g. <em>SimpleVarStore</em> or <em>SimpleFuncStore</em>.</p>
</div>
<div class="listingblock">
<div class="title">Examples</div>
@@ -1202,7 +1223,7 @@ The value on the left side of <code class="blue">=</code> must be an identifier.
</div>
</div>
<div class="paragraph">
<p>In other words, the selector operator evaluates the expression (<code>&lt;select-expression&gt;</code>) on the left-hand side of the <code>?</code> symbol; it then compares the result obtained with the values listed in the <code>&lt;match-list&gt;&#8217;s. If the comparision find a match with a value in a match-list, the associated `&lt;case-multi-expression&gt;</code> is evaluted, and its result will be the final result of the selection operation.</p>
<p>In other words, the selector operator evaluates the expression (<code>&lt;select-expression&gt;</code>) on the left-hand side of the <code>?</code> symbol; it then compares the result obtained with the values listed in the <code>&lt;match-list&gt;&#8217;s. If the comparision finds a match with a value in a match-list, the associated `&lt;case-multi-expression&gt;</code> is evaluted, and its result will be the final result of the selection operation.</p>
</div>
<div class="paragraph">
<p>The match lists are optional. In that case, the position, from left to right, of the <code>&lt;selector-case&gt;</code> is used as match-list. Of course, that only works if the select-expression results in an integer.</p>
@@ -1213,13 +1234,21 @@ The value on the left side of <code class="blue">=</code> must be an identifier.
<div class="listingblock">
<div class="title">Examples</div>
<div class="content">
<pre class="rouge highlight"><code data-lang="go"><span class="m">1</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span> <span class="p">{</span><span class="s">"b"</span><span class="p">}</span> <span class="c">// returns "b"</span>
<span class="m">10</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span> <span class="p">{</span><span class="s">"b"</span><span class="p">}</span> <span class="o">::</span> <span class="p">{</span><span class="s">"c"</span><span class="p">}</span> <span class="c">// returns "c"</span>
<span class="m">10</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span><span class="p">[</span><span class="no">true</span><span class="p">,</span> <span class="m">2</span><span class="o">+</span><span class="m">8</span><span class="p">]</span> <span class="p">{</span><span class="s">"b"</span><span class="p">}</span> <span class="o">::</span> <span class="p">{</span><span class="s">"c"</span><span class="p">}</span> <span class="c">// returns "b"</span>
<span class="m">10</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span><span class="p">[</span><span class="no">true</span><span class="p">,</span> <span class="m">2</span><span class="o">+</span><span class="m">8</span><span class="p">]</span> <span class="p">{</span><span class="s">"b"</span><span class="p">}</span> <span class="o">::</span><span class="p">[</span><span class="m">10</span><span class="p">]</span> <span class="p">{</span><span class="s">"c"</span><span class="p">}</span> <span class="c">// error: "... case list in default clause"</span>
<span class="m">10</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span><span class="p">[</span><span class="m">10</span><span class="p">]</span> <span class="p">{</span><span class="n">x</span><span class="o">=</span><span class="s">"b"</span> <span class="n">but</span> <span class="n">x</span><span class="p">}</span> <span class="o">::</span> <span class="p">{</span><span class="s">"c"</span><span class="p">}</span> <span class="c">// returns "b"</span>
<span class="m">10</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span><span class="p">[</span><span class="m">10</span><span class="p">]</span> <span class="p">{</span><span class="n">x</span><span class="o">=</span><span class="s">"b"</span><span class="p">;</span> <span class="n">x</span><span class="p">}</span> <span class="o">::</span> <span class="p">{</span><span class="s">"c"</span><span class="p">}</span> <span class="c">// returns "b"</span>
<span class="m">10</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span> <span class="p">{</span><span class="s">"b"</span><span class="p">}</span> <span class="c">// error: "... no case catches the value (10) of the selection expression</span></code></pre>
<pre class="rouge highlight"><code data-lang="go"><span class="s">`&gt;&gt;&gt;`</span> <span class="p">[</span><span class="n">blue</span><span class="p">]</span><span class="s">`1 ? {"a"} : {"b"}`</span>
<span class="p">[</span><span class="n">green</span><span class="p">]</span><span class="s">`b`</span>
<span class="s">`&gt;&gt;&gt;`</span> <span class="p">[</span><span class="n">blue</span><span class="p">]</span><span class="s">`10 ? {"a"} : {"b"} :: {"c"}`</span>
<span class="p">[</span><span class="n">green</span><span class="p">]</span><span class="s">`c'
[green]`</span><span class="o">&gt;&gt;&gt;</span><span class="s">` [blue]`</span><span class="m">10</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span><span class="p">[</span><span class="no">true</span><span class="p">,</span> <span class="m">2</span><span class="o">+</span><span class="m">8</span><span class="p">]</span> <span class="p">{</span><span class="s">"b"</span><span class="p">}</span> <span class="o">::</span> <span class="p">{</span><span class="s">"c"</span><span class="p">}</span><span class="s">`
[green]`</span><span class="n">b</span><span class="s">`
`</span><span class="o">&gt;&gt;&gt;</span><span class="s">` [blue]`</span><span class="m">10</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span><span class="p">[</span><span class="no">true</span><span class="p">,</span> <span class="m">2</span><span class="o">+</span><span class="m">8</span><span class="p">]</span> <span class="p">{</span><span class="s">"b"</span><span class="p">}</span> <span class="o">::</span><span class="p">[</span><span class="m">10</span><span class="p">]</span> <span class="p">{</span><span class="s">"c"</span><span class="p">}</span><span class="s">`
[red]`</span><span class="n">Parse</span> <span class="n">Error</span><span class="o">:</span> <span class="p">[</span><span class="m">1</span><span class="o">:</span><span class="m">34</span><span class="p">]</span> <span class="k">case</span> <span class="n">list</span> <span class="n">in</span> <span class="k">default</span> <span class="n">clause</span><span class="s">`
[green]`</span><span class="o">&gt;&gt;&gt;</span><span class="s">` [blue]`</span><span class="m">10</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span><span class="p">[</span><span class="m">10</span><span class="p">]</span> <span class="p">{</span><span class="n">x</span><span class="o">=</span><span class="s">"b"</span> <span class="n">but</span> <span class="n">x</span><span class="p">}</span> <span class="o">::</span> <span class="p">{</span><span class="s">"c"</span><span class="p">}</span><span class="s">`
[green]`</span><span class="n">b</span><span class="s">`
`</span><span class="o">&gt;&gt;&gt;</span><span class="s">` [blue]`</span><span class="m">10</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span><span class="p">[</span><span class="m">10</span><span class="p">]</span> <span class="p">{</span><span class="n">x</span><span class="o">=</span><span class="s">"b"</span><span class="p">;</span> <span class="n">x</span><span class="p">}</span> <span class="o">::</span> <span class="p">{</span><span class="s">"c"</span><span class="p">}</span><span class="s">`
[green]`</span><span class="n">b</span><span class="s">`
`</span><span class="o">&gt;&gt;&gt;</span><span class="s">` [blue]`</span><span class="m">10</span> <span class="err">?</span> <span class="p">{</span><span class="s">"a"</span><span class="p">}</span> <span class="o">:</span> <span class="p">{</span><span class="s">"b"</span><span class="p">}</span><span class="s">`
[red]`</span><span class="n">Eval</span> <span class="n">Error</span><span class="o">:</span> <span class="p">[</span><span class="m">1</span><span class="o">:</span><span class="m">3</span><span class="p">]</span> <span class="n">no</span> <span class="k">case</span> <span class="n">catches</span> <span class="n">the</span> <span class="n">value</span> <span class="p">(</span><span class="m">10</span><span class="p">)</span> <span class="n">of</span> <span class="n">the</span> <span class="n">selection</span> <span class="n">expression</span><span class="s">`
</span></code></pre>
</div>
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</div>
@@ -1490,7 +1519,7 @@ The value on the left side of <code class="blue">=</code> must be an identifier.
</div>
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Last updated 2024-05-10 06:38:03 +0200
Last updated 2024-05-11 20:13:17 +0200
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