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Postings from August 2012
On 8/31/2012 7:20 AM, Ricardo Signes wrote:
> * Peter Scott <Peter@PSDT.com> [2012-08-30T01:40:35]
> I feel the same way, which is why I originally and again proposed the
> much simpler behavior discussed in this thread.
>> If I wanted to construct a subroutine that smartmatched arguments that
>> could really be of any type, I'd be so paranoid every time I looked at
>> the code that I'd be forever reconsidering what all possible argument
>> types could do. Is the type dispatch table for ~~ obvious enough that
>> people can internalize it rapidly without having to refer to it
>> constantly? So far, I haven't.
> ...because this paragraph made it sound like you were only considering the old
> one. The new one is tiny and (I thought) both easy to remember and to intuit.
> Could you let me know whether you've written ths message with it in mind?
Both actually, but for different reasons (see below).
> Again, the current discussion does not allow $x ~~ $simple_value.
I'm afraid I have gotten lost among the proposals. The original one in
this thread included:
Any Simple $a eq $b
got whittled down to "unambigous Num/str", but I missed the part where
that was removed altogether. FC's post of restricting ~~ to *only*
Scalar/Simple was where I chimed in, although perhaps I missed a nuance
in how he proposed special-casing it.
>> If there were a natural intuitive interpretation of ~~ I think it would
>> have emerged from all this brainstorming by now.
> I think one has. Are you specifically saying that the "short table smart
> match" is not good? Because it's too complex, or too simple?
>
> It was:
>
> $x ~~ undef
> $x ~~ $overloaded_object
> $x ~~ sub {}
> $x ~~ regex
> ...or fail
I objected to the original/current table for the same reasons AFAICT as
you do. I'm afraid that your proposal, while much smaller and probably
memorable, if it doesn't include a Simple case, will spawn a neverending
chorus of "Why can't I do 'when (42)'?" That seems to be the *only* use
case that some people want ~~ for and it seems quite reasonable for them
to want it. Yet I can't see the Simple case working because of the
string/number dichotomy that has been hashed over and over. And if they
*can* do when(42) then they will want to do when($ULTIMATE_ANSWER) and
when(ULTIMATE_ANSWER) and if they can't, it becomes embarrassing to try
and explain why.
Despite heroic efforts by yourself and equally stellar minds, I think
this tunnel has no light at its end. IMHO. Sorry.
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