in reply to Re: localizing lexical without messing with tie ?
in thread localizing lexical without messing with tie ?

> local doesn't remove the magic — the variable is still tied in the block

argh you're right, I didn't test what I didn't expect... I would explicitly need to untie the localized var.

package NewStdScalar;
require Tie::Scalar;
 
@ISA = qw(Tie::StdScalar);
 
 
sub FETCH { return ${+shift}++ }
 
package main;
$\="\n";
$,="\t";
 
 
 
tie our $scalar, 'NewStdScalar';
 
sub prsc {print $scalar    };
$scalar=0;
 
prsc();
 
{
  local $scalar=42;
  # untie $scalar;  # uncomment this to make it work
  prsc();
  prsc();
  prsc();
  print $scalar; 
}
 
   
prsc();
__DATA__
0
42
43
44
45
1

[download]

Sorry, ATM I'm too tired to look further into the examples you posted, later more.

But I think I will go the simple way to exclude the use of tied variables by throwing a warning. Thx,

Cheers Rolf

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Re^3: localizing lexical without messing with tie ?
by ikegami (Patriarch) on Sep 08, 2010 at 17:01 UTC

    You don't seem to know what you're looking for. At the very least, it wasn't clearly communicated. Please clarify.

    Update: Maybe it's one of these:

    Override a global package variable for a static scope: 

    our $var = 'a';
{ my $var = 'x'; print "$var\n"; }  # x
print "$var\n";                     # a

    [download]
    my $var = 'a';
{ my $var = 'x'; print "$var\n"; }  # x
print "$var\n";                     # a

    [download]

    Override a global package variable for a dynamic scope: (Doesn't remove magic. Doesn't localise pos() except maybe on recent Perls.) 

    our $var = 'a';
sub f { print "$var\n"; }
{ local $var = 'x'; f(); }  # x
print "$var\n";             # a

    [download]

    Override a global package variable for a dynamic scope: 

    our $var = 'a';
sub f { print "$var\n"; }
{ local *var; *var = 'x'; f(); }  # x
print "$var\n";                   # a

    [download]

    Override a global lexical variable for a dynamic scope: 

    my $var = 'a';
sub f { print "$var\n"; }
{ ?????; $var = 'x'; f(); }  # x
print "$var\n";              # a

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[reply]

        see Re^2: localizing lexical without messing with tie ?.

        What do you call "passed variable"?

        As I said, an additional local untie does what I wanted.

        Doubtful. The untie isn't local. I've provided a solution that works where you used untie.

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