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37 lines
685 B
Markdown
37 lines
685 B
Markdown
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# wrappy
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Callback wrapping utility
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## USAGE
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```javascript
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var wrappy = require("wrappy")
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// var wrapper = wrappy(wrapperFunction)
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// make sure a cb is called only once
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// See also: http://npm.im/once for this specific use case
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var once = wrappy(function (cb) {
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var called = false
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return function () {
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if (called) return
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called = true
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return cb.apply(this, arguments)
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}
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})
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function printBoo () {
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console.log('boo')
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}
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// has some rando property
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printBoo.iAmBooPrinter = true
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var onlyPrintOnce = once(printBoo)
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onlyPrintOnce() // prints 'boo'
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onlyPrintOnce() // does nothing
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// random property is retained!
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assert.equal(onlyPrintOnce.iAmBooPrinter, true)
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```
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