$.map have no scope bind

[futurist]

var arr=[{a:1},{a:2}]
$.map(arr, function(){console.log(this)})

Always print window, window

While as

var arr=[{a:1},{a:2}]
$.each(arr, function(){console.log(this)})

Print right output: {a:1}, {a:2}

[ghost]

@futurist

I think $.map() is designed to work in this way intentionally.

The source code is shown as follows:

// $.each()
value = callback.call(elements[i], i, elements[i]);
// $.map()
value = callback(elements[i], i);

They are designed in a similar fashion as JQuery and the source code of JQuery is shown as follows:

// $.each()
value = callback.call( obj[ i ], i, obj[ i ] )
// $.map()
value = callback( elems[ i ], i, arg )

JQuery has mentioned that $.map() refers to the global (window) object and $.each() refers to an Object even if it is a simple string or number value.