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Minor copyedit of rust_parser.html #9

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2 changes: 1 addition & 1 deletion rust_parser.html
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Expand Up @@ -105,7 +105,7 @@ <h2 id="lexing">Lexing</h2>
Num(<span class="dt">u64</span>),
}</code></pre></div>
<p>I could have used more enum values to distinguish between <code>+</code> and <code>*</code> and the different types of parentheses, but instead I just store the character. It probably would have been a good idea to add another integer to each <code>LexItem</code> that stores the location in the input at which the token starts. That would make error reporting more useful. Instead I will just use the position in the token stream for my errors. Since I’m the only user of this program, I will only be angry at myself, so it’s okay.</p>
<p>The language I want to parse is very simple to lex. Except numbers, all tokens are just a single character long. So instead of complicated things with regular expressions. Instead I iterate over the characters of my input <code>String</code> and use a <code>match</code> do create a <code>LexItem</code>. The <code>match</code> statement is really handy here, since I can specify multiple alternatives for the same case with <code>|</code> and ranges of characters are also supported.</p>
<p>The language I want to parse is very simple to lex. Except numbers, all tokens are just a single character long. So instead of doing complicated things with regular expressions, I iterate over the characters of my input <code>String</code> and use a <code>match</code> do create a <code>LexItem</code>. The <code>match</code> statement is really handy here, since I can specify multiple alternatives for the same case with <code>|</code> and ranges of characters are also supported.</p>
<div class="sourceCode"><pre class="sourceCode rust"><code class="sourceCode rust"><span class="kw">fn</span> lex(input: &amp;<span class="dt">String</span>) -&gt; <span class="dt">Result</span>&lt;<span class="dt">Vec</span>&lt;LexItem&gt;, <span class="dt">String</span>&gt; {
<span class="kw">let</span> <span class="kw">mut</span> result = <span class="dt">Vec</span>::new();

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