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POJavascript regex library with incremental testing
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copied!<p>I'm looking for a JavaScript library (ideally a node.js package) that can check if a string matches a regular expression incrementally (i.e. one character at a time), and return indeterminate results. For example, say I have the following regex:</p> <pre><code>j.*s.* </code></pre> <p>And I want to test the string "javascript". I would like an API similar to the following:</p> <pre><code>var iregex = new IncrementalRegex('j.*s.*'); var matcher = iregex.createMatcher(); matcher.append('j'); matcher.test(); //returns "possible match" matcher.append('a'); matcher.test(); //returns "possible match" matcher.append('v'); matcher.append('a'); matcher.append('s'); matcher.test(); //returns "match found" matcher.append('ript'); matcher.test(); //returns "match found" </code></pre> <p>Whereas if I tested the string "foo", I would expect something like this:</p> <pre><code>var matcher2 = iregex.createMatcher(); matcher.append('f'); matcher.test(); //returns "no match possible" //At this point I wouldn't bother appending "oo" because I know that no match is possible. </code></pre> <p>EDIT: To be clear, append is building up the string being tested. A new matcher starts out testing against the empty string, and after a matcher.append('foo') it matches against foo. appendToString or buildUpString might have been better names to use.</p> <p>Also, I have one idea of how this could potentially be done, but I haven't fully thought it through yet. Perhaps it is possible to build a "Potential match" regex from the original regex that will match strings if and only if they are the beginning of a string the original regex matches.</p>

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