Allow circular lists in MAP and FOR-EACH for SRFI-1 compatibility
|Reported by:||cowan||Owned by:||cowan|
|Component:||WG1 - Core||Keywords:|
Allow circular lists as the list arguments to map and for-each. If all arguments are circular, these procedures will not terminate unless the mapping procedure forces a non-local exit. The result of map is not circular. Implementations that stop when the shortest list runs out and don't make gratuitous tests shouldn't have a problem with this: R5RS allows, R6RS forbids, and R7RS requires this behavior.