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    function Redirect 3

    Summary

    The function keyword can be used to define a function inside an expression.

    Keyword
    Implemented in: JavaScript 1.5
    ECMA Version: ECMA-262, Edition 3

    Syntax

    function [name]([param1[, param2[, ..., paramN]]]) {
       statements
    }

    Parameters

    name
    The function name. Can be omitted, in which case the function is anonymous. The name is only local to the function body.
    paramN
    The name of an argument to be passed to the function. A function can have up to 255 arguments.
    statements
    The statements which comprise the body of the function.

    Description

    A function expression is very similar to and has almost the same syntax as a function declaration (see function for details). See Functions for information on the differences between function statements and function expressions.

    Examples

    The following example defines an unnamed function and assigns it to x. The function returns the square of its argument:

    var x = function(y) {
       return y * y;
    };
    

    Named function expression

    If you want to refer to the current function inside the function body, you need to create a named function expression. This name is then local only to the function body (scope). This also avoids using the non-standard arguments.callee property.

    var math = {
      'factorial': function factorial(n) {
        if (n <= 1)
          return 1;
        return n * factorial(n - 1);
      }
    };
    

    See also

    Document Tags and Contributors

    Contributors to this page: Sheppy
    Last updated by: Sheppy,