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Postings from March 2022
On 8/3/22 17:25, Karl Williamson wrote: > On 3/8/22 07:38, Graham Knop wrote: >> On Fri, Mar 4, 2022 at 4:29 PM Paul "LeoNerd" Evans >> <leonerd@leonerd.org.uk> wrote: >>> >>> After further discussion with PSC, we'd like to keep moving this >>> forward. There's still time to add new functions to builtin:: in time >>> for 5.36, and it would be nice to get these in. >>> >>> We agree that they should not be named "isnumber" and "isstring", >>> mostly because of your concerns about leading people to think they do >>> something that they don't. >>> >>> I'd like to suggest you write up an RFC on this request, perhaps >>> beginning with the names >>> >>> builtin::was_originally_number >>> builtin::was_originally_string >>> >>> They're sufficiently long and unwieldy as to mildly discourage people >>> from using them except when absolutely necessary (read: on JSON >>> serialisers and similar), and the name itself doesn't suggest it tells >>> you current information about the actual type of a value, merely tells >>> you the history on how it started. >> >> I've created an RFC PR: https://github.com/Perl/RFCs/pull/13 >> >> In the RFC, I'm using the names builtin::created_as_number and >> builtin::created_as_string. Justification is included in the RFC, but >> I think these better match what we want their return values to >> represent. And I personally, was_originally_number feels really >> awkward as a function name. The names could still be changed of >> course; I'm not overly attached to what I've chosen. > > I think "created_as..." are better than previous suggestions It has just occurred to me that we may be missing the point focusing in that it-was-created-as-a-whatever thing too much. If a scalar was created as, say, a number, it keeps being a number. That perl is able to transparently convert that value into something else when needed and cache the result, doesn't change the fact that it is still a number. From a functional point of view, I think that was is needed is a set of functions to check the type of a scalar and another set of functions (a la looks_like_number) to check whether it can be converted into something else: builtin::isa_number builtin::looks_like_number etc. One important point here is that neither "isa_number", neither "looks_like_number" are influenced by the private type flags (or the scalar history, which is an uninteresting thing, right?): $a = "7"; say isa_number($a), looks_like_number($a); $b = $a+1; say isa_number($a), looks_like_number($a); # same resultsThread Previous | Thread Next