function highlight(input) {
	var output = '',
		string = false,
		lineComment = false,
		capVar = false,
		warnings = [];
	for (var i = 0; i < input.length; i++) {
		var c = input[i];
		if (c == '/' && input[i + 1] == '/') {
			lineComment = true;
			output += '<span class="comment">' + c + input[++i];
		} else if (lineComment) {
			if (c == '\n') {
				lineComment = false;
				output += '</span>';
			}
			output += c;
		} else if (c === string) {
			string = false;
			output += c + '</span>';
		} else if (string && c == '\n') {
			warnings.push([i, 'Unexpected line end, string literal not terminated.']);
			string = false;
			output += '</span>' + c;
		} else if (string) {
			if (c == '\\') output += '<span class="escape">';
			output += c;
			if (c == '\\') {
				output += c = input[++i];
				if (c == 'u') {
					output += c = input[++i];
					if (c == '{') {
						while ((c = input[++i]) && c != '}') output += c;
						output += '}';
					} else output += input[++i] + input[++i] + input[++i];
				} else if (c == 'x') output += input[++i] + input[++i];
				output += '</span>';
			}
		} else if (c == '"' || c == "'") {
			string = c;
			output += '<span class="string">' + c;
		} else if (c != c.toLowerCase() && (input[i - 1] || ' ').match(/\W/)) {
			capVar = true;
			output += '<span class="cap-var">' + c;
		} else if (capVar && c.match(/\W/)) {
			capVar = false;
			output += '</span>';
			i--;
		} else if (input.substr(i, 9) == 'prototype') {
			output += '<span class="prototype">prototype</span>';
			i += 8;
		} else if (input.substr(i, 8) == 'function') {
			var j = i,
				l = c;
			while (l = input[--j]) {
				if (l == '=') {
					var end = output.length + j - i;
					output = output.substring(0, end) + '<span class="operator assigns">=</span>' + output.substr(end + 1);
					j = end;
					while (output[--j].match(/\s/)) end--;
					var start = end;
					j++;
					while (j && !output.replaceAll('<span class=', '<span-class-')[--j].match(/[\s=(]/)) start--;
					output = output.substring(0, start) + '<span class="function-name">' + output.substring(start, end) + '</span>' + output.substr(end);
					break;
				} else if (!l.match(/\s/)) break;
			}
			output += '<span class="keyword">function</span>';
			i += 6;
			var stop = ++i + input.substr(i).indexOf('(');
			if (!stop) return warnings.push([i, 'Function arguments not found.']);
			if ((c = input[++i]).match(/\s/)) {
				output += c + '<span class="function-name">';
				while ((c = input[++i]) && c != '(') output += c;
				output += '</span>';
			}
			while (i < stop) output += input[++i];
			output += '<span class="punctuation">(</span>';
			var argString = '';
			while ((c = input[++i]) && c != ')') argString += c;
			output += argString.replace(/[^\s,]+/g, '<span class="arguments">$&</span>').replaceAll(',', '<span class="punctuation">,</span>') + '<span class="punctuation">)</span>';
		} else if (',.;()[]{}'.indexOf(c) != -1) {
			output += '<span class="punctuation">' + c + '</span>';
		} else output += c;
	}
	console.log(output);
	console.log(warnings);
	return output.split('\n');
}