In my time of PL/1 programming, I liked the PUT DATA statement during debugging: It outputs the name of a variable, together with its value: 

x=5; y=7;
PUT DATA (x,y);

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outputs 
x=5 y=7

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I wonder whether something similar can be implemented in Perl. Of course the naive approach 
use Data::Dumper;
sub show {
  local $Data::Dumper::Terse=1;
  local $SHOW::expr=shift;
  local $SHOW::val=eval { $expr };
  $SHOW::expr . ($@ ? " throws exception: $@" 
                    : ('='.Dumper($SHOW::expr)));
}

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fails if $expr contains my variables from the calling context. I guess a useful implementation would have been to interfere somehow with the compiler (in a similar way the debugger is behaving). Could someone give me some pointer on how this could be implemented? Or maybe is there already some module on CPAN which I could use?

-- 
Ronald Fischer <ynnor@mm.st>

In reply to PL/1's PUT DATA in Perl - is this possible? by rovf

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