Question

I want to make a function that automatically turns every “Math” function global

example:

floor = Math.floor

This allows me to do this:

alert(floor(2.5))

The example above works perfectly (it alerts “2”), but I can’t seem to find a way to automate this process for every function in the “Math” object. I looked on the internet and I tried to make something myself but… nothing works.

answer:

(function(a,b){for(b in a=Object.getOwnPropertyNames(Math))this[a[b]]=Math[a[b]]})()

Answer 1

Actually you might think you could just loop over all the properties from the Math object and turn any function into a global one (by copying its reference):

for( var prop in Math ) {
    if( typeof Math[ prop ] === 'function' ) {
        window[ prop ] = Math[ prop ];
    }
}

This would work.. if the word would wouldn’t be here 🙂

We can discover the problem with Object.getOwnPropertyDescriptor:

console.log( Object.getOwnPropertyDescriptor(Math, 'floor') );

..and as we can see, all methods are set to enmuerable false.

---

edit

I actually forgot about Object.getOwnPropertyNames. You indeed could get all property names with that method, like

Object.getOwnPropertyNames(Math).forEach(function(name) {
    if( typeof Math[name] === 'function' )
        window[name] = Math[name];
});