implementation: use split for template parsing (#10)

Author: cho45

lib/micro-template.js

@@ -8,22 +8,23 @@ const template = function (id, data) {
 		let name = id, string = /^[\w\-]+$/.test(id) ? me.get(id): (name = 'template(string)', id); // no warnings
 		let line = 1;
 		const body = (
-			"try { " +
-				(me.variable ?  "let " + me.variable + " = __this.stash;" : "with (__this.stash) { ") +
-					"__this.ret += '"  +
-					string.
-						replace(/<%/g, '\x11').replace(/%>/g, '\x13'). // if you want other tag, just edit this line
-						replace(/\\(?![^\x11\x13]+?\x13)/g, '\\x5c'). // escape backslash of outside of tag
-						replace(/'(?![^\x11\x13]+?\x13)/g, '\\x27'). // escape single quote of outside of tag
-						replace(/^\s*|\s*$/g, '').
-						replace(/\n|\r\n/g, function () { return "';\n__this.line = " + (++line) + "; __this.ret += '\\n" }).
-						replace(/\x11=raw(.+?)\x13/g, "' + ($1) + '").
-						replace(/\x11=(.+?)\x13/g, "' + __this.escapeHTML($1) + '").
-						replace(/\x11(.+?)\x13/g, "'; $1; __this.ret += '") +
-				"'; " + (me.variable ? "" : "}") + "return __this.ret;" +
-			"} catch (e) { throw new Error('TemplateError: ' + e + ' (on " + name + "' + ' line ' + __this.line + ')'); } " +
-			"//@ sourceURL=" + name + "\n" // source map
-		).replace(/__this\.ret \+= '';/g, '').replace(/\x11/g, '<%').replace(/\x13/g, '%>');
+			`try { ` +
+				(me.variable ?  `let ${me.variable} = __this.stash;` : `with (__this.stash) { /*start*/`) +
+				string.trim().split(/(<%.+?%>)/g).map(part =>
+					part.startsWith('<%=raw') && part.endsWith('%>') ? `/*raw*/__this.ret+=(${part.slice(6, -2)});` :
+					part.startsWith('<%=') && part.endsWith('%>')    ? `/*=*/__this.ret+=__this.escapeHTML(${part.slice(3, -2)});` :
+					part.startsWith('<%') && part.endsWith('%>')     ? `/* */${part.slice(2, -2)};` :
+					(
+						part = part.replace(/\\/g, "\\\\")
+								.replace(/'/g, "\\'")
+								.replace(/\n|\r\n/g, () => `\\n';\n__this.line = ${++line}; __this.ret += '`),
+						part ? `/*+*/__this.ret+='${part}';` : ''
+					)
+				).join('') +
+				`/*end*/ ${me.variable ? "" : "}"} return __this.ret;` +
+			`} catch (e) { throw new Error('TemplateError: ' + e + ' (on ${name} line ' + __this.line + ')'); }` +
+			`//@ sourceURL=template.js\n`
+		);
 		const func = new Function("__this", body);
 		const map  = { '&' : '&amp;', '<' : '&lt;', '>' : '&gt;', '\x22' : '&#x22;', '\x27' : '&#x27;' };
 		const escapeHTML = function (string) { return (''+string).replace(/[&<>\'\"]/g, function (_) { return map[_] }) };