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Re: Pre-RFC: ${^ENGLISH_NAME} aliases for punctuation variables

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Leon Timmermans
July 8, 2022 18:42
Re: Pre-RFC: ${^ENGLISH_NAME} aliases for punctuation variables
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On Sat, Oct 30, 2021 at 1:47 AM Dan Book <> wrote:

> Currently, each punctuation variable has an $ENGLISH_NAME alias available
> for readability. But this has a couple problems: it's only available if you
> "use English;" which does not provide a direct indication of the variables
> it's related to in the code, and was a significant performance penalty in
> older versions of Perl; these issues leading to not much use of the module
> and thus the knowledge of their existence has not become widespread; so
> average Perl programmers finding $CHILD_ERROR in Perl code are likely not
> to know it's an alias for $? or that it's a built-in variable at all, thus
> reducing its effective readability instead of increasing it.
> Proposed by haarg in is to add
> aliases like ${^CHILD_ERROR}, using the built-in variable form used for
> other more recently added built-in variables.
> This has a few advantages: it provides a readable indication of its
> purpose like those provided by "use English"; it is clearly a built-in
> variable to those who have come across that syntax, and clearly not a
> regular variable to those who don't; and it doesn't require an opt-in such
> as "use English" as this syntax is already available for Perl to add any
> new variable names.
> The risks are primarily that it doesn't end up being useful and in the
> process uses up a bunch of built-in variable names - but reusing the
> existing English names for any other purpose strikes me as a poor idea
> regardless. It also is likely to be considered uglier than English
> variables, due to the extra punctuation required.
> This may also be a tangential way to work toward addressing the problem of
> rarely-used punctuation variables preventing the use of syntax for other
> purposes, such as discussed in

I did a first stab at implementing this, and it didn't quite work because
of the way many magical variables are lazily set up on first usage. I would
expect implementing this to involve some serious refactoring of that area
of the code.


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