Enumeration Management

GB.GetEnum	Returns the current enumeration state.
GB.ListEnum	Lists all enumerators that enumerate a specified object.
GB.NextEnum	Returns the next enumerator.
GB.StopAllEnum	Stops all enumerators that enumerate a specified object.
GB.StopEnum	Stops the current enumeration.

Overview

Enumerations are managed in the _next special method.

This method is called at the start of the enumeration, and at each loop iteration, to retrieve the first or the next element.

Enumeration State

GB.GetEnum gives you a pointer to a enumeration buffer. Use this buffer to store the state of the enumeration. You can store up to 16 bytes into this buffer.

Note that the buffer is initialized with zeros at the beginning of the enumeration, so that you can detect when _next is called at the start of the enumeration.

When the end of the enumeration is reached, use the GB.StopEnum function to warn the interpreter, and returns immediately from the implementation function.

Updating Enumeration State

If you want to destroy one element of the enumeration, you must use GB.ListEnum and GB.NextEnum to update the state of current iterators.

If you want to entirely clear the enumerable object, then you must use GB.StopAllEnum to stop all current iterators.