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Ticket 129: About value returned by mutation procedures

2011-05-19 15:44:00
WG1 - Core
alexshinn
major
medernac
duplicate
source
closed
2011-01-12 15:45:18
defect

Why not have "no value" instead of "unspecified one" in mutations procedures (set!, set-car!, set-cdr!, vector-set!, vector-fill!)

By convention, the value returned by a mutation procedure is unspecified.

to

By convention, mutation procedures return no value.

PS: is there any implementation returning the value being stored ?

aag
2011-01-13 01:30:57

In MIT Scheme, set! returns the previous value of the variable.

medernac
2011-01-13 15:44:20

Thanks for bringing this to mind about MIT-Scheme, as at least one implementation returns a value it is indeed not wise to push such a change (at least for 'set!').

alexshinn
2011-05-19 15:44:00
resolution␣duplicate
statusnewclosed

Duplicate of #68.