in reply to Re: How Perl decides where a variable ends and text starts: Match variables in string interpolation
in thread How Perl decides where a variable ends and text starts: Match variables in string interpolation

I was almost certain that I had seen a counter-example, but you are right Variable names.
Bill
  • Comment on Re^2: How Perl decides where a variable ends and text starts: Match variables in string interpolation

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Re^3: How Perl decides where a variable ends and text starts: Match variables in string interpolation
by davido (Cardinal) on Jul 23, 2021 at 17:02 UTC

    There are symbolic refs, but you have to stay in the symbolic ref world. If you create ${'1_'} as a symbolic reference, you have to continue to refer to it symbolically only. Perl barfs if you try to use it as $1_ later on. Here's a working example, though:

    {
    no strict 'refs';
    ${'1_'} = 100;
    print ${'1_'}, "\n";
}

    [download]

    If you go on to dump the %main:: hash you'll see the package global $1_ does exist. Perl's syntax just doesn't support it as anything but a symbolic ref, I think.


    Dave

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      A more extreme example: 

      Win8 Strawberry 5.8.9.5 (32)  Fri 07/23/2021 20:17:49
C:\@Work\Perl\monks
>perl -Mstrict -Mwarnings -l

{
    no strict 'refs';
    ${'@-%^#$!+'} = 'Yikes!';
    print ${'@-%^#$!+'};
}

print "%main:: $main::{'@-%^#$!+'}";

^Z
Yikes!
%main:: *main::@-%^#$!+

      [download]
      Same behavior under Strawberry 5.30.3.1 64-bit.

      Give a man a fish:  <%-{-{-{-<

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