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copied!<p>Emphasizing what Gumbo said.</p> <p>Also, if a language has a real elif / elsif / elseif (say, a "real" else-if instruction, instead of a kind of nested chaining hidden away by formatting), then the compiler can easly emit a single node in an Abstract Syntax Tree (or similar, see <a href="http://en.wikipedia.org/wiki/Abstract_syntax_tree" rel="nofollow noreferrer">http://en.wikipedia.org/wiki/Abstract_syntax_tree</a>) instead of nesting them. </p> <p>To give an example:</p> <p>Say in C/C++ you have:</p> <pre><code>if (a) { X } else if (b) { Y } else if (c) { Z } else { 0 } </code></pre> <p>Then the compiler will build an AST-node like this:</p> <pre><code> a / \ X b / \ Y c / \ Z 0 </code></pre> <p>But if the language of choice has a real if-else:</p> <pre><code>if (a) { X } elif (b) { Y } elif (c) { Z } else { 0 } </code></pre> <p>Then the AST could more easily look like this:</p> <pre><code> (a--b--c) / / / \ X Y Z 0 </code></pre> <p>In such a language, an "if else" would only be possible if braces are not mandatory:</p> <pre><code>if (a) { X } elif (b) { Y } else if (c) { // syntax error "missing braces" if braces mandatory Z } else { 0 } </code></pre> <p>Corresponding AST (<em>if braces are not mandatory</em>):</p> <pre><code> (a--b) / / \ X Y c / \ Z 0 </code></pre> <p>This could make CFG-Analysis (<a href="http://en.wikipedia.org/wiki/Control_flow_graph" rel="nofollow noreferrer">http://en.wikipedia.org/wiki/Control_flow_graph</a>) easier to <em>implement</em> (though there might be no actual optimization benefit; so imho it'd just benefit the lazy programmer :D).</p>

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