Generic log level

log.js

var logLevels = {
	error: {
		prio: 0, // lower has priority
		method: "error"
	},
	warning: {
		prio: 1,
		method: "warn"
	},
	info: {
		prio: 2,
		method: "log"
	}
};

var logLevelPrio = logLevels["info"].prio;

var log = function(level, msg) {
	if(level in logLevels) {
		if(logLevels[level].prio <= logLevelPrio) { // lower has priority
			console[logLevels[level].method](msg);
		}
	}
};

var setLogLevel = function(level) {
	logLevelPrio = level in logLevels ?
		logLevels[level].prio : -1;
};

["info", "warning", "error", "none"].forEach(function(level) {
	console.log("log level is", level);
	setLogLevel(level);
	log("info", "info message");
	log("warning", "warning message");
	log("error", "error message");
	console.log();
});

Outputs

log level is info
info message
warning message
error message

log level is warning
warning message
error message

log level is error
error message

log level is none