[perl #108780] overload::StrVal and qr//

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[perl #108780] overload::StrVal and qr//

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From:

Father Chrysostomos

Date:

January 22, 2012 12:58

Subject:

[perl #108780] overload::StrVal and qr//

Message ID:

rt-3.6.HEAD-14510-1327265876-1128.108780-75-0@perl.org

# New Ticket Created by  Father Chrysostomos 
# Please include the string:  [perl #108780]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org:443/rt3/Ticket/Display.html?id=108780 >


According to the overload documentation, overload::StrVal returns the string that "" would return in the absence of string overloading.

But this isn’t actually the case:

    $\ = "\n";
    use overload;
    no overloading;
    print qr//;                   # prints (?^:)
    print overload::StrVal(qr//); # prints Regexp=REGEXP(0x803e50)

qr// thingies are not actually using overloading.

overload::StrVal pretends that they are.

The overloading pragma knows they are not.

Should one of overload::StrVal and overloading.pm change to match the other?

Or should the we just document this oddity?

This discrepancy is unfortunate, as it prevents this type of simplification:

commit 8f6eeb4da8aeaa8cbb3b291181bdac4515d92e2d
Author: Father Chrysostomos <sprout@cpan.org>
Date:   Wed Jan 18 13:03:32 2012 -0800

    In overload::AddrRef, use ‘no overloading’
    
    This speeds this up by about 13 times.

diff --git a/lib/overload.pm b/lib/overload.pm
index a2797e7..2cd98bb 100644
--- a/lib/overload.pm
+++ b/lib/overload.pm
@@ -113,17 +113,8 @@ sub Method {
 }
 
 sub AddrRef {
-  my $package = ref $_[0];
-  return "$_[0]" unless $package;
-
-  local $@;
-  local $!;
-  require Scalar::Util;
-  my $class = Scalar::Util::blessed($_[0]);
-  my $class_prefix = defined($class) ? "$class=" : "";
-  my $type = Scalar::Util::reftype($_[0]);
-  my $addr = Scalar::Util::refaddr($_[0]);
-  return sprintf("%s%s(0x%x)", $class_prefix, $type, $addr);
+  no overloading;
+  "$_[0]";
 }
 
 *StrVal = *AddrRef;
---
Flags:
    category=core
    severity=low
---
Site configuration information for perl 5.15.6:

Configured by sprout at Mon Jan 16 08:41:41 PST 2012.

Summary of my perl5 (revision 5 version 15 subversion 6) configuration:
  Commit id: bdd2b37b5c6133a3b8647bb19d63f9598457d4d4
  Platform:
    osname=darwin, osvers=10.5.0, archname=darwin-2level
    uname='darwin pint.local 10.5.0 darwin kernel version 10.5.0: fri nov 5 23:20:39 pdt 2010; root:xnu-1504.9.17~1release_i386 i386 '
    config_args='-de -Dusedevel -DDEBUGGING'
    hint=recommended, useposix=true, d_sigaction=define
    useithreads=undef, usemultiplicity=undef
    useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
    use64bitint=undef, use64bitall=undef, uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cc', ccflags ='-fno-common -DPERL_DARWIN -DDEBUGGING -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include',
    optimize='-O3 -g',
    cppflags='-fno-common -DPERL_DARWIN -DDEBUGGING -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include'
    ccversion='', gccversion='4.2.1 (Apple Inc. build 5664)', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='env MACOSX_DEPLOYMENT_TARGET=10.3 cc', ldflags =' -fstack-protector -L/usr/local/lib'
    libpth=/usr/local/lib /usr/lib
    libs=-ldbm -ldl -lm -lutil -lc
    perllibs=-ldl -lm -lutil -lc
    libc=, so=dylib, useshrplib=false, libperl=libperl.a
    gnulibc_version=''
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=bundle, d_dlsymun=undef, ccdlflags=' '
    cccdlflags=' ', lddlflags=' -bundle -undefined dynamic_lookup -L/usr/local/lib -fstack-protector'

Locally applied patches:
    

---
@INC for perl 5.15.6:
    /usr/local/lib/perl5/site_perl/5.15.6/darwin-2level
    /usr/local/lib/perl5/site_perl/5.15.6
    /usr/local/lib/perl5/5.15.6/darwin-2level
    /usr/local/lib/perl5/5.15.6
    /usr/local/lib/perl5/site_perl
    .

---
Environment for perl 5.15.6:
    DYLD_LIBRARY_PATH (unset)
    HOME=/Users/sprout
    LANG=en_US.UTF-8
    LANGUAGE (unset)
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin:/usr/local/bin
    PERL_BADLANG (unset)
    SHELL=/bin/bash

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