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@philipwalton
Last active Jan 3, 2016
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What would you like to do?
Async events handling strategies
// host library code
program()
.initStuff()
.then(function() {
dispatcher.emit('beforeRenderPost')
})
.then(function() {
dispatcher.emit('afterRenderPost')
})
.then(function() {
dispatcher.emit('beforeWritePost')
})
.then(function() {
dispatcher.emit('afterWritePost')
})
.catch(errorHandler)
// now the user's code can simply be the following and the host logic
// will wait until their async function is finished before continuing
dispatcher.on('beforeRenderPost', doSomethingAsyncToPost)
@philipwalton
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philipwalton commented Jan 14, 2014

would basically need to check against the expected Function.length to define if you should wait for callback call or not

I originally considered this. Like, if the callback function's .length property is one greater than the emitter's arguments.length property, assume async, but that won't work 100% of the time. Sometimes a callback will make use of the arguments object for ...rest parameter type situations, so it gets a bit hairy.

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