return result;
};
}

// Usage
var canOnlyFireOnce = once(function() {
console.log('Fired!');
});

canOnlyFireOnce(); // "Fired!"
canOnlyFireOnce(); // nada

return a.href;
};
})();

// Usage
getAbsoluteUrl('/something');

// Used to resolve the decompiled source of functions
var fnToString = Function.prototype.toString;

// Used to detect host constructors (Safari > 4; really typed array specific)
var reHostCtor = /^[object .+?Constructor]$/;

// Compile a regexp using a common native method as a template.
// We chose Object#toString because there's a good chance it is not being mucked with.
var reNative = RegExp('^' +
// Coerce Object#toString to a string
String(toString)
// Escape any special regexp characters
.replace(/[.+?^${}()|[]\/\]/g,'\$&')
// Replace mentions of toString with `.?to keep the template generic. // Replace thing likefor ...` to support environments like Rhino which add extra info
// such as method arity.
.replace(/toString|(function).?(?=\()| for .+?(?=\])/g,'$1.?') + '$'
);

function isNative(value) {
var type = typeof value;
return type == 'function'
// Use Function#toString to bypass the value's own toString method
// and avoid being faked out.
? reNative.test(fnToString.call(value))
// Fallback to a host object check because some environments will represent
// things like typed arrays as DOM methods which may not conform to the
// normal native pattern.
: (value && type == 'object' && reHostCtor.test(toString.call(value))) || false;
}

// export however you want
module.exports = isNative;
}());

// Usage
isNative(alert); // true
isNative(myCustomFunction); // false

// Then call as a function
Sheet(".stats { position: relative ; top: 0px }") ;