[ENH] ifNotEmptyCleans
Avi Bryant
avi at beta4.com
Thu Sep 30 11:24:26 UTC 2004
On Sep 30, 2004, at 12:41 PM, stéphane ducasse wrote:
> For me I do not understand what it means to require an argument, in
> this case this is not
> ifNotEmpty: [do that]
> but ifNotEmpty: [do that with self]
> and the message does not tell that at all
>
> and why we have that for ifNotEmpty and not for ifTrue: and isNil:
Because in the case of ifTrue: and ifNil: (as well as ifFalse:), if the
block is evaluated then you know exactly what the receiver is, so
there's no need to pass it in.
This is also mostly true for #ifEmpty:, in that you know that you've
got an empty collection, and that's probably all you care about. In
the case of #ifNotNil: or #ifNotEmpty:, however, there are interesting
things about the receiver (for #ifNotNil:, what the instance is, for
#ifNotEmpty:, what instances it contains) that you *don't* know, and so
passing the receiver into the block is very useful.
I generally agree with you about the message names, in that I'd rather
see ifNotEmptyDo: (to match #ifNotNilDo:) as a distinct method from
#ifNotEmpty:. However, there's a compatibility issue here - other
dialects expect #ifNotNil: and #ifNotEmpty: to take a 1-arg block, and
we should probably follow suit. As it is I have to avoid using either
message if I want my code to be portable, which is a shame.
Avi
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