game tree location

CQL has a few filters that describe where the current position is in the game tree:

filter name	example	description
initial	initial	current position is first position of game
mainline	mainline	current position is in a main line
movenumber	movenumber 20 30	move number of current position is in range
terminal	terminal	current position has no successors
variation	variation	current position is in a variation

Note: by "variation" here we always exclude the mainline - there is no "mainline variation" in CQL terminology.

variations parameter and game location filters

If the variations parameter is set then the tree considered in the above filters is the full game tree. However, if the variations parameter is not set, the the tree considered is only the single mainline branch.