Re^9: ref eq "REF"

in fact, this is exactly my point

I thought your point was that a scalar is a scalar is a scalar; a scalar that's a reference should still be thought of as a scalar. That's a notion I'll agree with, even though I don't have any problem with ref returning REF. The reason I say hash keys are a separate issue is because, I repeat, hash keys are not a scalar values, they are string values.

Hash keys accept only string values because it was a lowercase-p-perl design decision to make them string values.

I have no direct knowledge of why they chose to implement Perl's hashes using string values as keys, but I can easily see it as both an implementation choice and a language choice. Using arbitrary scalar values as hash keys adds complexity to both areas. With something as fundamental as hashes, I can easily understand the desire to keep it simple.

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Re^10: ref eq "REF" by gaal (Parson) on Oct 19, 2004 at 10:00 UTC
I see it as the same issue because "string value" doesn't have (much of) a place in the nomenllature of Perl. I mean in typical usage; in the docs; in tutorials an well-known books. People are educated to think of $var as a scalar (which is a scalar etc.), and then when they use a reference as a hash key it loses its magic and they are suprised. There are other places where stringification occurs. For example, if you create a file from a variable that holds a reference, and then use `readdir` to attempt to recover it, obviously it's going to lose its magic. I don't think that suprises anyone as much <g> but that's precisely because you are unPerlifying your data. I take back my claim about the genesis of string-only hash keys. You're right: I don't know how the decision was made either. We both recognize simplicity; my gripe was about consistency (which, when lacking, often causes loss of simplicity elsewhere). (Paranthetically: in Java, references can be hash keys. Of course, Java hashes are nowhere near as elegant to use as in Perl, so I don't know whose point of view this supports. Then again I think we've more or less come to see eye to eye on this, no?)	[reply] [d/l]

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Re^10: ref eq "REF"
by gaal (Parson) on Oct 19, 2004 at 10:00 UTC

There are other places where stringification occurs. For example, if you create a file from a variable that holds a reference, and then use readdir to attempt to recover it, obviously it's going to lose its magic. I don't think that suprises anyone as much <g> but that's precisely because you are unPerlifying your data.

I take back my claim about the genesis of string-only hash keys. You're right: I don't know how the decision was made either. We both recognize simplicity; my gripe was about consistency (which, when lacking, often causes loss of simplicity elsewhere).

(Paranthetically: in Java, references can be hash keys. Of course, Java hashes are nowhere near as elegant to use as in Perl, so I don't know whose point of view this supports. Then again I think we've more or less come to see eye to eye on this, no?)

[reply]
[d/l]