elisp.js/elisp/trace.js

exports.printStackTrace = function() {
    var callstack = [];
    var isCallstackPopulated = false;
    try {
	i.dont.exist+=0; //doesn't exist- that's the point
    } catch(e) {
	if (e.stack) { //Firefox
	    var lines = e.stack.split("\n");
	    for (var i=0, len=lines.length; i<len; i++) {
		if (lines[i].match(/^\s*[A-Za-z0-9\-_\$]+\(/)) {
	            callstack.push(lines[i]);
		}
	    }
	    //Remove call to printStackTrace()
	    callstack.shift();
	    isCallstackPopulated = true;
	}
	else if (window.opera && e.message) { //Opera
	    var lines = e.message.split("\n");
	    for (var i=0, len=lines.length; i<len; i++) {
		if (lines[i].match(/^\s*[A-Za-z0-9\-_\$]+\(/)) {
		    var entry = lines[i];
	            //Append next line also since it has the file info
	            if (lines[i+1]) {
			entry += " at " + lines[i+1];
			i++;
	            }
	            callstack.push(entry);
		}
	    }
	    //Remove call to printStackTrace()
	    callstack.shift();
	    isCallstackPopulated = true;
	}
    }
    if (!isCallstackPopulated) { //IE and Safari
	var currentFunction = arguments.callee.caller;
	while (currentFunction) {
	    var fn = currentFunction.toString();
	    var fname = fn.substring(fn.indexOf("function") + 8, fn.indexOf("(")) || "anonymous";
	    callstack.push(fname);
	    currentFunction = currentFunction.caller;
	}
    }
    print('stack trace', callstack.join("\n\n"));
};