in reply to Tkx after coderef problem

What do you think amperstand operator does ? You're to call subs that dont exist

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Re^2: Tkx after coderef problem
by huck (Prior) on Jun 02, 2018 at 15:08 UTC

    Im not sure id call my use of ampersand an operator here. If i have the following 

    my $code=sub{print "hi\n";}; 
&{$code};

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    the &{} part references the code section of its contents and calls it, much like if i have 
    my $var='hi'; 
my $ref=\$var; 
${$ref}='there'; 
print "$var\n";

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    the ${}part references the scalar section of its contents allowing me to set it with the assign statement.

    as for subs not existing, remember that for at least 1 and up to 5 times the call succeeded and the sub/coderef did exist, and at the end of MainLoop the sub/coderef still exists.

    To show that the coderef still exists and is valid if i changed the "debug" statment at the end to 

      if ( $tkxfsr->{after}{$afterid}{sub}) { 
      print 'sub:'.$tkxfsr->{after}{$afterid}{sub}."\n";
      &{$tkxfsr->{after}{$afterid}{sub}}(); 
      &{$tkxfsr->{after}{$afterid}{sub}};
      }

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    on ubuntu it still fails as it did before but now it prints out the next two items in the queue after printing 'sub:'.....

    Edit:add output 

    encapulated sub=0
SCMD 1527954135_123_c1 hi
LIST 1527954135_123_c1 hi 1----------
LIST 1527954135_123_c1 hi 2----------
LIST 1527954135_123_c1 hi 3----------
sub:CODE(0x9cdda24)
LIST 1527954135_123_c1 hi 4----------
LIST 1527954135_123_c1 hi 5----------

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      which sub is rAising invalid command? What command where? What is undefinex at time of sub call?

      The word is operator. If it's not an operator what is it a puppy?

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        The word is operator. If it's not an operator what is it a puppy?

        It is not a puppy, it is a "dereferencing symbol"

        https://perldoc.perl.org/perlref.html
        "Because of being able to omit the curlies for the simple case of $$x , people often make the mistake of viewing the dereferencing symbols as proper operators"

        "which sub is rAising invalid command?" It is the Tkx::after command that is raising invalid command when its time has arrived to actually call its argument.

        "What command where?"The command is the one created by $tkxfsr->{after}{$afterid}{sub}=sub{ ...}; since the code address match.

        "What is undefinex at time of sub call? " Nothing is actually undefined at the time of the call, but for some reason the execution part of Tkx:after thinks it is.

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