<!doctype html> <title>CodeMirror: Mode-Changing Demo</title> <meta charset="utf-8"/> <link rel=stylesheet href="../doc/docs.css"> <link rel="stylesheet" href="../lib/codemirror.css"> <script src="../lib/codemirror.js"></script> <script src="../mode/javascript/javascript.js"></script> <script src="../mode/scheme/scheme.js"></script> <style type="text/css"> .CodeMirror {border: 1px solid black;} </style> <div id=nav> <a href="http://codemirror.net"><h1>CodeMirror</h1><img id=logo src="../doc/logo.png"></a> <ul> <li><a href="../index.html">Home</a> <li><a href="../doc/manual.html">Manual</a> <li><a href="https://github.com/codemirror/codemirror">Code</a> </ul> <ul> <li><a class=active href="#">Mode-Changing</a> </ul> </div> <article> <h2>Mode-Changing Demo</h2> <form><textarea id="code" name="code"> ;; If there is Scheme code in here, the editor will be in Scheme mode. ;; If you put in JS instead, it'll switch to JS mode. (define (double x) (* x x)) </textarea></form> <p>On changes to the content of the above editor, a (crude) script tries to auto-detect the language used, and switches the editor to either JavaScript or Scheme mode based on that.</p> <script> var editor = CodeMirror.fromTextArea(document.getElementById("code"), { mode: "scheme", lineNumbers: true }); var pending; editor.on("change", function() { clearTimeout(pending); pending = setTimeout(update, 400); }); function looksLikeScheme(code) { return !/^\s*\(\s*function\b/.test(code) && /^\s*[;\(]/.test(code); } function update() { editor.setOption("mode", looksLikeScheme(editor.getValue()) ? "scheme" : "javascript"); } </script> </article>