count should accept a parameter fn, where fn is a predicate function.

add a remove function that takes in the object to remove from the collection

add an indexOf method that takes in an object and returns its index within the collection

Since a string is an array of characters, it would helpful to provide the asEnumerable() extension method for strings as well. This method would create an array of characters via the following:

var arr = [];

for(var i = 0; i < str.length; i++)
{
    arr[i] = str.charAt(i);
}

You could then have access to any of the asEnumerable functions (any, count, select, where.. etc).

var str = "abcdef";
str.asEnumerable().dropLast(4);
//result: "ab"

After which it becomes necessary to seamlessly convert back to a string. This could be accomplished by overriding the toString() method of the array that is created when asEnumerable() is called.

var arr = ["a", "b"];
var result = arr.join('');
// result: "ab"

This would allow syntax like str.asEnumerable().dropLast(3).toString() 😄

integrate webpack