Bachir Soussi Chiadmi ac58a24f5c added bower, gulp | 7 years ago | |
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.. | ||
LICENSE | 7 years ago | |
README.md | 7 years ago | |
once.js | 7 years ago | |
package.json | 7 years ago |
Only call a function once.
var once = require('once')
function load (file, cb) {
cb = once(cb)
loader.load('file')
loader.once('load', cb)
loader.once('error', cb)
}
Or add to the Function.prototype in a responsible way:
// only has to be done once
require('once').proto()
function load (file, cb) {
cb = cb.once()
loader.load('file')
loader.once('load', cb)
loader.once('error', cb)
}
Ironically, the prototype feature makes this module twice as complicated as necessary.
To check whether you function has been called, use fn.called
. Once the
function is called for the first time the return value of the original
function is saved in fn.value
and subsequent calls will continue to
return this value.
var once = require('once')
function load (cb) {
cb = once(cb)
var stream = createStream()
stream.once('data', cb)
stream.once('end', function () {
if (!cb.called) cb(new Error('not found'))
})
}