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21. High-level API Reference
YModule module
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isOnline_async()
Checks if the module is currently reachable, without raising any error.
js
function isOnline_async( callback , context )
If there are valid cached values for the module, that have not yet expired, the device is considered
reachable. No exception is raised if there is an error while trying to contact the requested module.
This asynchronous version exists only in Javascript. It uses a callback instead of a return value in order
to avoid blocking Firefox Javascript VM that does not implement context switching during blocking I/O
calls.
Parameters :
callback callback function that is invoked when the result is known. The callback function receives three
arguments: the caller-specific context object, the receiving module object and the boolean result
context caller-specific object that is passed as-is to the callback function
Returns :
nothing : the result is provided to the callback.
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