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Ticket 309: Allow circular lists in MAP and FOR-EACH for SRFI-1 compatibility

2012-10-07 12:48:52
WG1 - Core
cowan
major
cowan
fixed
source
closed
2011-12-03 02:16:03
defect

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.

statusnewdecided

The WG voted to adopt this proposal.

owneralexshinncowan
statusdecidedwriting
resolutionfixed
statuswritingclosed