[perl #79584] perldsc question for Mr Christiansen

# New Ticket Created by  Edward Strinden 
# Please include the string:  [perl #79584]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=79584 >


Subject: perldsc question for Mr Christiansen
Message-Id: <5.12.1_1264_1290419875@ed>
Reply-To: edwardstrinden@gmail.com
To: perlbug@perl.org


This is a bug report for perl from edwardstrinden@gmail.com,
generated with the help of perlbug 1.39 running under perl 5.12.1.

Subject: request for clarification perldsc
Message-Id: <5.12.1_3324_1290418699@ED>
Reply-To: edwardstrinden@gmail.com
To: tchrist@perl.com


This is a bug report for perl from edwardstrinden@gmail.com,
generated with the help of perlbug 1.39 running under perl 5.12.1.


-----------------------------------------------------------------

Mr. Christiansen,

I'm having trouble understanding the difference
between @{ $AoA[0] } = @array and $AoA[0] = [ @array ]

You say in the perl data structures cookbook that
in the case with the dereference on the lefthand
side would have the effect of clobbering whatever
data could already exist in the reference.

Am I missing something in interpreting this as a
technique to save storage and nothing more? Would
this technique create a memory leak from the data
referenced by $$AoA[0]?

With thanks,

Edward

-----------------------------------------------------------------
---
Flags:
     category=docs
     severity=wishlist
---
Site configuration information for perl 5.12.1:

Configured by 1 at Thu Jul 29 16:39:48 2010.

Summary of my perl5 (revision 5 version 12 subversion 1) configuration:

   Platform:
     osname=MSWin32, osvers=5.1, archname=MSWin32-x86-multi-thread
     uname='Win32 strawberryperl 5.12.1.0 #1 Thu Jul 29 10:08:11 2010 i386'
     config_args='undef'
     hint=recommended, useposix=true, d_sigaction=undef
     useithreads=define, usemultiplicity=define
     useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
     use64bitint=undef, use64bitall=undef, uselongdouble=undef
     usemymalloc=n, bincompat5005=undef
   Compiler:
     cc='gcc', ccflags =' -s -O2 -DWIN32 -DHAVE_DES_FCRYPT  
-DUSE_SITECUSTOMIZE -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS 
-fno-strict-aliasing -mms-bitfields -DPERL_MSVCRT_READFIX',
     optimize='-s -O2',
     cppflags='-DWIN32'
     ccversion='', gccversion='4.4.3', gccosandvers=''
     intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
     d_longlong=undef, longlongsize=8, d_longdbl=define, longdblsize=12
     ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='long 
long', lseeksize=8
     alignbytes=8, prototype=define
   Linker and Libraries:
     ld='g++', ldflags ='-s -L"C:\strawberry\perl\lib\CORE" 
-L"C:\strawberry\c\lib"'
     libpth=C:\strawberry\c\lib C:\strawberry\c\i686-w64-mingw32\lib
     libs=-lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg32 
-ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid -lws2_32 -lmpr 
-lwinmm -lversion -lodbc32 -lodbccp32 -lcomctl32
     perllibs=-lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool 
-lcomdlg32 -ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid 
-lws2_32 -lmpr -lwinmm -lversion -lodbc32 -lodbccp32 -lcomctl32
     libc=, so=dll, useshrplib=true, libperl=libperl512.a
     gnulibc_version=''
   Dynamic Linking:
     dlsrc=dl_win32.xs, dlext=dll, d_dlsymun=undef, ccdlflags=' '
     cccdlflags=' ', lddlflags='-mdll -s -L"C:\strawberry\perl\lib\CORE" 
-L"C:\strawberry\c\lib"'

Locally applied patches:


---
@INC for perl 5.12.1:
     C:/strawberry/perl/site/lib
     C:/strawberry/perl/vendor/lib
     C:/strawberry/perl/lib
     .

---
Environment for perl 5.12.1:
     CYGWIN=tty
     HOME (unset)
     LANG (unset)
     LANGUAGE (unset)
     LD_LIBRARY_PATH (unset)
     LOGDIR (unset)
     
PATH=C:\WINDOWS;C:\WINDOWS\system32;C:\WINDOWS\system32\Wbem;C:\Program 
Files\OpenSSH\bin;C:\Perl\c\bin;C:\Perl\site\bin;C:\Perl\perl\bin;C:\strawberry\c\bin;C:\strawberry\perl\site\bin;C:\strawberry\perl\bin
     PERL_BADLANG (unset)
     SHELL (unset)
---
Flags:
     category=docs
     severity=low
---
Site configuration information for perl 5.12.1:

Configured by 1 at Thu Jul 29 16:39:48 2010.

Summary of my perl5 (revision 5 version 12 subversion 1) configuration:

   Platform:
     osname=MSWin32, osvers=5.1, archname=MSWin32-x86-multi-thread
     uname='Win32 strawberryperl 5.12.1.0 #1 Thu Jul 29 10:08:11 2010 i386'
     config_args='undef'
     hint=recommended, useposix=true, d_sigaction=undef
     useithreads=define, usemultiplicity=define
     useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
     use64bitint=undef, use64bitall=undef, uselongdouble=undef
     usemymalloc=n, bincompat5005=undef
   Compiler:
     cc='gcc', ccflags =' -s -O2 -DWIN32 -DHAVE_DES_FCRYPT  
-DUSE_SITECUSTOMIZE -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS 
-fno-strict-aliasing -mms-bitfields -DPERL_MSVCRT_READFIX',
     optimize='-s -O2',
     cppflags='-DWIN32'
     ccversion='', gccversion='4.4.3', gccosandvers=''
     intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
     d_longlong=undef, longlongsize=8, d_longdbl=define, longdblsize=12
     ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='long 
long', lseeksize=8
     alignbytes=8, prototype=define
   Linker and Libraries:
     ld='g++', ldflags ='-s -L"C:\strawberry\perl\lib\CORE" 
-L"C:\strawberry\c\lib"'
     libpth=C:\strawberry\c\lib C:\strawberry\c\i686-w64-mingw32\lib
     libs=-lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg32 
-ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid -lws2_32 -lmpr 
-lwinmm -lversion -lodbc32 -lodbccp32 -lcomctl32
     perllibs=-lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool 
-lcomdlg32 -ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid 
-lws2_32 -lmpr -lwinmm -lversion -lodbc32 -lodbccp32 -lcomctl32
     libc=, so=dll, useshrplib=true, libperl=libperl512.a
     gnulibc_version=''
   Dynamic Linking:
     dlsrc=dl_win32.xs, dlext=dll, d_dlsymun=undef, ccdlflags=' '
     cccdlflags=' ', lddlflags='-mdll -s -L"C:\strawberry\perl\lib\CORE" 
-L"C:\strawberry\c\lib"'

Locally applied patches:


---
@INC for perl 5.12.1:
     C:/strawberry/perl/site/lib
     C:/strawberry/perl/vendor/lib
     C:/strawberry/perl/lib
     .

---
Environment for perl 5.12.1:
     CYGWIN=tty
     HOME (unset)
     LANG (unset)
     LANGUAGE (unset)
     LD_LIBRARY_PATH (unset)
     LOGDIR (unset)
     
PATH=C:\WINDOWS;C:\WINDOWS\system32;C:\WINDOWS\system32\Wbem;C:\Program 
Files\OpenSSH\bin;C:\Perl\c\bin;C:\Perl\site\bin;C:\Perl\perl\bin;C:\strawberry\c\bin;C:\strawberry\perl\site\bin;C:\strawberry\perl\bin
     PERL_BADLANG (unset)
     SHELL (unset)

• [perl #79584] perldsc question for Mr Christiansen by Edward Strinden
• Re: [perl #79584] perldsc question for Mr Christiansen by Eric Brine