| 1 | # wrappy
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| 2 |
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| 3 | Callback wrapping utility
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| 4 |
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| 5 | ## USAGE
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| 6 |
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| 7 | ```javascript
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| 8 | var wrappy = require("wrappy")
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| 9 |
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| 10 | // var wrapper = wrappy(wrapperFunction)
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| 11 |
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| 12 | // make sure a cb is called only once
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| 13 | // See also: http://npm.im/once for this specific use case
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| 14 | var once = wrappy(function (cb) {
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| 15 | var called = false
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| 16 | return function () {
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| 17 | if (called) return
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| 18 | called = true
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| 19 | return cb.apply(this, arguments)
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| 20 | }
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| 21 | })
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| 22 |
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| 23 | function printBoo () {
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| 24 | console.log('boo')
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| 25 | }
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| 26 | // has some rando property
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| 27 | printBoo.iAmBooPrinter = true
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| 28 |
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| 29 | var onlyPrintOnce = once(printBoo)
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| 30 |
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| 31 | onlyPrintOnce() // prints 'boo'
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| 32 | onlyPrintOnce() // does nothing
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| 33 |
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| 34 | // random property is retained!
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| 35 | assert.equal(onlyPrintOnce.iAmBooPrinter, true)
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| 36 | ```
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