I'm trying to load audio with XMLHttpRequests and AudioContext, my code looks like this:
class AudioExample
audioContext: null
init: ->
AudioContext = window.AudioContext || window.webkitAudioContext
@audioContext = new AudioContext!
# r = xmlhttprequest magic
r.onload = (e) ->
rr = e.target #XMLHttpRequest{response: ArrayBuffer, song: Object, si: Object}
@audioContext.decodeAudioData rr.response, (buffer) ->
# ...
The error is TypeError: Cannot read property 'decodeAudioData' of undefined.
When I console.log the audioContext I get a valid audioContext object, so why is it undefined on code execution?
It's a problem with bound functions; you can diagnose it by putting a console.log @ inside r.load = (e) -> ....
The solution is to bind r.onload handler using ~>:
r.onload = (e) ~> ...
Check LiveScript docs for Bound Functions.