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6.1 Module Implementation in Javascript
6.2 Conditional Module Implmentation in javascript

6 Implementing Javascript Modules

Warning: the material in this section is unstable and likely to change.

6.1 Module Implementation in Javascript

 (require (planet dyoo/js-vm:1:7/lang/js-impl/js-impl))
This module allows the definition of modules whose implementations are written in Javascript.

As an example, the following two files provide an implementation of double in Javascript:
  #lang planet dyoo/js-vm:1:7/js-impl
  (require-js "double.js")
  (provide double)

// double.js

EXPORTS['double'] =

    new types.PrimProc('double', 1, false, false, function(x) {

        return jsnums.multiply(x, 2)});

Any module implemented with (planet dyoo/js-vm:1:7/lang/js-impl/js-impl) will provide bindings that require a Javascript context.

6.2 Conditional Module Implmentation in javascript

 (require (planet dyoo/js-vm:1:7/lang/js-impl/js-conditional))

Any module implemented with (planet dyoo/js-vm:1:7/lang/js-conditional/js-conditional) can run either in a Racket or Javascript context.