History

Rich Trott e313c0286b tools: update to ESLint 3.2.2 PR-URL: https://github.com/nodejs/node/pull/7999 Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: Roman Reiss <me@silverwind.io> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Johan Bergström <bugs@bergstroem.nu>		2016-08-09 21:19:02 -07:00
..
LICENSE	tools: update eslint to v1.10.3	2016-01-13 23:15:39 +01:00
README.md	tools: update eslint to v1.10.3	2016-01-13 23:15:39 +01:00
package.json	tools: update to ESLint 3.2.2	2016-08-09 21:19:02 -07:00
wrappy.js	tools: update eslint to v1.10.3	2016-01-13 23:15:39 +01:00

README.md

wrappy

Callback wrapping utility

USAGE

var wrappy = require("wrappy")

// var wrapper = wrappy(wrapperFunction)

// make sure a cb is called only once
// See also: http://npm.im/once for this specific use case
var once = wrappy(function (cb) {
  var called = false
  return function () {
    if (called) return
    called = true
    return cb.apply(this, arguments)
  }
})

function printBoo () {
  console.log('boo')
}
// has some rando property
printBoo.iAmBooPrinter = true

var onlyPrintOnce = once(printBoo)

onlyPrintOnce() // prints 'boo'
onlyPrintOnce() // does nothing

// random property is retained!
assert.equal(onlyPrintOnce.iAmBooPrinter, true)