JavaScript constant

Given the name of a constant this function will return the constant's associated value

function constant (name) {
    // Given the name of a constant this function will return the constant's associated value  
    // 
    // version: 1109.2015
    // discuss at: http://phpjs.org/functions/constant    // +   original by: Paulo Freitas
    // +   improved by: Brett Zamir (http://brett-zamir.me)
    // *     example 1: constant('IMAGINARY_CONSTANT1');
    // *     returns 1: null
    var clssPos = 0,        clssCnst = null;
    if ((clssPos = name.indexOf('::')) !== -1) {
        clssCnst = name.slice(clssPos + 2);
        name = name.slice(0, clssPos);
    } 
    if (this.window[name] === undefined) {
        return null;
    }
    if (clssCnst) {        return this.window[name][clssCnst];
    }
    return this.window[name];
}

external links: original PHP docs | raw js source

Examples

Running

1	constant('IMAGINARY_CONSTANT1');

Should return

null

Dependencies

No dependencies, you can use this function standalone.

Open syntax issues

php.js uses JsLint to help us keep our code consistent and prevent some common bugs.

Eventually we want all code to pass or at least take into consideration most fixes suggested by JsLint, following this JsLint configuration we’ve decided on.

Authors

Thanks to the following developers, you get to have constant goodness in JavaScript.

Paulo Freitas ( original )
Brett Zamir ( improved )

Comments

Add Comment

Name

Website

Title

Content

Use:

[CODE]
your_stuff('here');
[/CODE]

for proper code formatting
By submitting code here you are allowing us to use it in php.js hence dual licensing it under the MIT and GPL licenses

Brett Zamir
21 Jun '10

@Paulo: I think Kevin wants to avoid automatically importing PHP constants (whether as globals or on the namespaced object). If a user wants them, they can follow the notes at http://phpjs.org/functions/get_defined_constants:839 to get them in scope, but this function constant() could still be useful without them in the case of user-defined constants.

Paulo Freitas
19 Jun '10

Hmm, this one should require get_defined_constants(), no? When I wrote I think that the get_defined_constants() doesn't exist yet, but for now it should be useful to do things like constant('DATE_W3C'). :)

Contribute a New function

JavaScript constant

Examples

Dependencies

Open syntax issues

Authors

More functions

Support us