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POFaster alternative to eval?
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copied!<p>I'm dealing with a web app that uses a home-grown templating system that lets Perl code be embedded in HTML. These statements are executed by the template parser at run-time using <code>eval EXPR</code>.</p> <p>This is very flexible, but these statements are scattered everywhere, and get executed a <em>lot</em>. <code>eval EXPR</code> (as opposed to <code>eval BLOCK</code>) requires Perl to fire up the interpreter each time, and my profiling reveals that they're a reasonably significant source of slowdown.</p> <p>Many of the embedded Perl statements are very simple. For example, a template might have a line like this:</p> <pre><code><p>Welcome, . </code></pre> <p>Or:</p> <pre><code><p>Ticket number  has been generated. </code></pre> <p>That is, they're just calling object methods. There are more complicated ones, too, though.</p> <p>I'm hoping to optimize this, and so far have two ideas, both of which are terrible. The first is to rewrite all templates to replace simple calls with tokens like <code>USER:NAME</code> and <code>USER:GENERATETICKETNUMBER</code>, which the parser could then scan for and invoke the appropriate object method. But then instead of dealing with templates that mix HTML and Perl, I would have templates that mix HTML, Perl, and tokens.</p> <p>The second idea is to try to parse the embedded Perl, figure out what the statement wants to do, and, if it's simple enough, call the appropriate object method via a symbolic reference. This is obviously insane.</p> <p>Is there some logical solution I'm overlooking?</p>

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