wrappy

Callback wrapping utility

USAGE

  1. var wrappy = require("wrappy")
  3. // var wrapper = wrappy(wrapperFunction)
  5. // make sure a cb is called only once
  6. // See also: http://npm.im/once for this specific use case
  7. var once = wrappy(function (cb) {
  8.   var called = false
  9.   return function () {
  10.     if (called) return
  11.     called = true
  12.     return cb.apply(this, arguments)
  13.   }
  14. })
  16. function printBoo () {
  17.   console.log('boo')
  18. }
  19. // has some rando property
  20. printBoo.iAmBooPrinter = true
  22. var onlyPrintOnce = once(printBoo)
  24. onlyPrintOnce() // prints 'boo'
  25. onlyPrintOnce() // does nothing
  27. // random property is retained!
  28. assert.equal(onlyPrintOnce.iAmBooPrinter, true)