# getCallbackFromHandle method

Function getCallbackFromHandle (CallbackHandle handle)

Get a tear-off of a named top-level or static callback represented by a handle.

The `handle` argument must not be null.

If `handle` is not a valid handle returned by PluginUtilities.getCallbackHandle, null is returned. Otherwise, a tear-off of the callback associated with `handle` is returned.

## Implementation

    static Function getCallbackFromHandle(CallbackHandle handle) {
      assert(handle != null, "'handle' must not be null.");
      return _backwardCache.putIfAbsent(
          handle, () => _getCallbackFromHandle(handle.toRawHandle()));
    }