?node_id=3989;HIT=readonly;re=N
Just what is 'readonly' in Perl and Perl 6?
Readonly variable
Module Readonly
What is the difference between the constant construct in Perl and the Readonly construct in Perl?
Reliability of SvREADONLY

Faster way to readonly are Attribute::Constant, Data::Lock, Scalar::Readonly, 

use Scalar::Readonly qw/ readonly_on /;
use Devel::Peek qw/ Dump /;
my $f=66;
readonly_on($f);
Dump($f);
__END__
SV = IV(0x99ba38) at 0x99ba3c
  REFCNT = 1
  FLAGS = (PADMY,IOK,READONLY,pIOK)
  IV = 66

[download]

Scalar::Readonly::readonly also simply checks for SvREADONLY flag, and no others (no FAKE), so it'll be a false positive on HASH keys

In reply to Re^2: Readonly problems ( Scalar::Readonly::readonly ) by Anonymous Monk
in thread Readonly problems by runrig

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