It was my understanding that Deparse gives me a parser-eye view of the code; that it turns what I write into a canonical form that parses identically. So if I have a script, try.pl, I can do 
perl -MO=Deparse try.pl > try2.pl
perl try2.pl

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and get exactly the same result as I would get from just 
perl try.pl

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Having found a nifty way to get around the problem of being unable to modify a lexical in the same statement as it is declared, I wanted to see how the parser saw it. The original script: 
#!perl
use strict;
use warnings;

use Data::Dumper;

s/foo/bar/ for (my $d = 'Shakespear is the food');

print "$d\n";

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and its output: 
Shakespear is the bard

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The script Deparse generated: 
use Data::Dumper;
BEGIN {${^WARNING_BITS} = "UUUUUUUUUUUU"}
use strict 'refs';
foreach $_ (my $d = 'Shakespear is the food') {
    s/foo/bar/;
}
print "$d\n";

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and its output: 
Name "main::d" used only once: possible typo at try2.pl line 7.
Use of uninitialized value in concatenation (.) or string at try2.pl l
+ine 7.

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What's broken? Deparse, or my understanding of it?

Update: Ok, so what I thought was nifty isn't so nifty. You can't use a lexical by name, but you can modify it easily enough with the usual 

(my $d = 'Shakespear is the food') =~ s/foo/bar/;

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Still, the predicate-for trick would give you a variable you could manipulate for something like 
/foo/ and $_ .= '1' for (my $d = 'Shakespear is the foo');

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Caution: Contents may have been coded under pressure.

In reply to Deparse broken or just misunderstood? by Roy Johnson

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