in reply to Re^6: Using pos() inside regexp (no /e)
in thread Using pos() inside regexp

I wonder if perhaps you're asking about something like this: 
#!/usr/bin/perl
use strict;
use warnings;
# 864348

$_='qwerty erk';
my $pos;

my $foo = $_ =~ s/r/
        $pos=pos(). "\n";
        print pos(); 
        print "\n"; 
        ++( pos() );
        print "\t" . pos() . "\n";
        print($pos . "\n")/gex;

print "Now, outside the regex, $pos";

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Output:

3
        4
3

8
        9
8

Now, outside the regex, 8

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(Note: as you wrote the one-liner in your previous, you wrote an illegal ref to $_; the $ does NOT need escaping in your one-liner.
... and I'm confused: "G" and "g" come and go in your posts... sometimes one; sometimes the other; and sometimes, not at all.)

Replies are listed 'Best First'.
Re^8: Using pos() inside regexp (no /e)
by braveghost (Acolyte) on Oct 10, 2010 at 15:58 UTC
    Yes! This is exactly the thing i talk about, pos() for next iteration of regexp is not changes. And looks like there is no way to change it, and this is realy meaningless because variable regexp save initial value of variable and use this value for search and another for replace results. 
     $ perl -MDevel::Peek -e "\$_='qwerty';Dump(\$_);s/[rt]/Dump(\$_);/ge;
+print Dump(\$_)"
SV = PV(0x801838) at 0x82fde0
  REFCNT = 1
  FLAGS = (POK,pPOK)
  PV = 0x201fe0 "qwerty"\0
  CUR = 6
  LEN = 8
SV = PVMG(0x823514) at 0x82fde0
  REFCNT = 1
  FLAGS = (SMG,POK,pPOK)
  IV = 0
  NV = 0
  PV = 0x201fe0 "qwerty"\0
  CUR = 6
  LEN = 8
  MAGIC = 0x2018d0
    MG_VIRTUAL = &PL_vtbl_mglob
    MG_TYPE = PERL_MAGIC_regex_global(g)
    MG_LEN = 3
SV = PVMG(0x823514) at 0x82fde0
  REFCNT = 1
  FLAGS = (SMG,POK,pPOK)
  IV = 0
  NV = 0
  PV = 0x201fe0 "qwerty"\0
  CUR = 6
  LEN = 8
  MAGIC = 0x2018d0
    MG_VIRTUAL = &PL_vtbl_mglob
    MG_TYPE = PERL_MAGIC_regex_global(g)
    MG_LEN = 4
SV = PVMG(0x823514) at 0x82fde0
  REFCNT = 1
  FLAGS = (SMG,POK,pPOK)
  IV = 0
  NV = 0
  PV = 0x2010d0 "qwey"\0
  CUR = 4
  LEN = 8
  MAGIC = 0x2018d0
    MG_VIRTUAL = &PL_vtbl_mglob
    MG_TYPE = PERL_MAGIC_regex_global(g)
    MG_LEN = -1

    [download]
    So, it seems my task can't be solved by using follow construction 
    $data =~s/([^\n]{16})/pos($data)=0;ch($1)/ge;

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    (Note: escaping of $ simbol is nessesary for bash 
    # perl -e "\$_='qwerty';s/r/print pos();/e;"
3

BUT

# perl -e "$_='qwerty';s/r/print pos();/e;"
syntax error at -e line 1, near ";="
Execution of -e aborted due to compilation errors.

# uname -v
Darwin Kernel Version 10.4.0: Fri Apr 23 18:28:53 PDT 2010; root:xnu-1
+504.7.4~1/RELEASE_I386

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    )
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      Take your "BUT" example and extend it:

      perl -e "$_='qwerty'; s/r/print pos(). \"\n\";/e; print $_;

      OUTPUT: 

      3
qwe1ty

      [download]

      Note the "1" (one) in the replaced output. Maybe you can go somewhere with this.

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        Again, escape of '$' is necessary for bash shell which used at unix-like system 
        perl -e "$_='qwerty'; s/r/print pos(). \"\n\";/e; print $_;"
syntax error at -e line 2, near "="
Execution of -e aborted due to compilation errors.

        [download]
        but then $ is escaped 
        perl -e "\$_='qwerty'; s/r/print pos(). \"\n\";/e; print \$_;"
3
qwe1ty

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        It seems you try your example under windows, and it is work fine there, but i'm macos user. 1(one) is returned by print function and s/// insert it because it is last return at executed section, this is clear, but it can be easily fix 
        perl -e "\$_='qwerty'; s/r/print pos(). \"\n\";\$&/e; print \$_;"
3
qwerty

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[d/l]
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