funcunit/site/node_modules/transpile/lib/es6_compiler.js

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var compilerMap = {
	'traceur': './clean_traceur_compile',
	'babel': './babel_compile'
};

module.exports = function(options){
	if(typeof options.transpile === "function") {
		return options.transpile;
	}

	var compilerName = (options && options.transpiler) || 'traceur';
	var moduleName = compilerMap[compilerName];

	return require(moduleName);
};