I'm seeking enlightenment! This is about the Perl debugger and lexicals ('my' variables). Here's a script: 

#! /usr/bin/perl -ws
use mytest2;
print mt2(55), "\n";

[download]

And here's the module it use's: 

#! /usr/bin/perl -w

package mytest2;

require Exporter;
our @ISA = qw( Exporter );
our @EXPORT = qw( mt2 );

my $a = 23;

sub mt2 {
  my $b = $_[0] * 2;
#  return $a + $b;
}

1;

[download]

My problem is this: With the return line in mt2() commented as shown, I run the top script via 'perl -d' and single-step to the first line of mt2() (that line hasn't executed yet). The debug command 'x $a' returns 'undef' - the debugger can't 'see' $a, even though it is declared earlier in the module file.

When the indicated line is uncommented, this isn't the case anymore -- the debugger reports the proper value of $a before the first line of mt2() is executed, even before it gets referenced or used (in the second line).

I can add code to reference the lexical vars in a module's subroutine that I can set a breakpoint in. But can I not access those lexicals directly? - anyway? - via the debugger?

In reply to Debugger and lexicals by lzipin

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