Neither.�� No two ways about it.�� #keysAndValuesDo:
However,
�� seq with: seq keys do: aBlock
and
�� seq withIndexDo: aBlock
do the same thing, so #withIndexDo: makes some sense.
This is not my opinion alone.�� I'm typing this on a machine
that has Squeak but not Pharo.�� In Squeak we find
doWithIndex: elementAndIndexBlock
������ "Use the new version with consistent naming"
������ ^ self withIndexDo: elementAndIndexBlock
"New" means since 1997.