Question

In Python, you can something like this:

>>> list(map(str.upper, ['foo','bar']))
['FOO', 'BAR']

I would like to be able to do something similar in javascript:

I’ve tried the following in Chrome using the native map implementation ( https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/map ):

['foo','bar'].map(String.prototype.toUpperCase)

['foo','bar'].map(String.prototype.toUpperCase.call)

Why doesn’t call work?
Is there any elegant way to do this or must I wrap toUpperCase in a callback function?
Thx

Answer 1

Modern browsers support this (although it is a recent addition)

var a = ['foo','bar'];
var b = a.map(String.toUpperCase);

alert(b[1]);

or even

var a = ['foo','bar'].map(String.toUpperCase);
alert(a[0]);

example: http://www.jsfiddle.net/xPsba/