Well, you could go with

use constant PADDING => 2;

my $col_width = PADDING + (
    sort {
        $b <=> $a
    } map {
        length
    } keys %list, map {
        @$_
    } values %lists
)[ 0 ]; ## Longest key or value
[download]

But in

use constant PADDING => 2;

my $col_width = PADDING + (
    sort {
        $b <=> $a
    } map {
        length
    } map {
        ref ? @$_ : $_
    } %lists
)[ 0 ]; ## Longest key or value
[download]

The line ref eq 'ARRAY' ? @$_ : $_ just says: if it($_) is a value (array) flatten it to a list, (which you already had in your own version), or if it is a key, pass it through untouched.

That avoids having to treat the keys and values separately, (and iterate the hash twice to generate them). In doing so it reduces the noise level a little further.

I've adopted it because I saw it saves a loop iteration. The second version there is now actually broken. It works if you add parens, so: ref () ? @$_ : $_


- Boldra

List::Util and Text::Table aren't available on my target platforms

What platform is that? List::Util is in the standard library. Everyone has it unless someone has gone to pathological efforts to reduce the size of the perl installation.

Activeperl 5.60

C:\>perl -V
Summary of my perl5 (revision 5 version 6 subversion 0) configuration:
  Platform:
    osname=MSWin32, osvers=4.0, archname=MSWin32-x86-multi-thread
    uname=''
    config_args='undef'
    hint=recommended, useposix=true, d_sigaction=undef
    usethreads=undef use5005threads=undef useithreads=define usemultip
+licity=def
ine
    useperlio=undef d_sfio=undef uselargefiles=undef
    use64bitint=undef use64bitall=undef uselongdouble=undef usesocks=u
+ndef
  Compiler:
    cc='cl', optimize='-O1 -MD -DNDEBUG', gccversion=
    cppflags='-DWIN32'
    ccflags ='-O1 -MD -DNDEBUG -DWIN32 -D_CONSOLE -DNO_STRICT -DHAVE_D
+ES_FCRYPT
 -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -DPERL_MSVCRT_READFIX'
    stdchar='char', d_stdstdio=define, usevfork=false
    intsize=4, longsize=4, ptrsize=4, doublesize=8
    d_longlong=undef, longlongsize=8, d_longdbl=define, longdblsize=10
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t',
+ lseeksize
=4
    alignbytes=8, usemymalloc=n, prototype=define
  Linker and Libraries:
    ld='link', ldflags ='-nologo -nodefaultlib -release  -libpath:"C:\
+Perl\lib\C
ORE"  -machine:x86'
    libpth="C:\Perl\lib\CORE"
    libs=  oldnames.lib kernel32.lib user32.lib gdi32.lib winspool.lib
+  comdlg32
.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib  netapi32.lib uui
+d.lib wsoc
k32.lib mpr.lib winmm.lib  version.lib odbc32.lib odbccp32.lib msvcrt.
+lib
    libc=msvcrt.lib, so=dll, useshrplib=yes, libperl=perl56.lib
  Dynamic Linking:
    dlsrc=dl_win32.xs, dlext=dll, d_dlsymun=undef, ccdlflags=' '
    cccdlflags=' ', lddlflags='-dll -nologo -nodefaultlib -release  -l
+ibpath:"C:
\Perl\lib\CORE"  -machine:x86'


Characteristics of this binary (from libperl):
  Compile-time options: MULTIPLICITY USE_ITHREADS PERL_IMPLICIT_CONTEX
+T PERL_IMP
LICIT_SYS
  Locally applied patches:
        ActivePerl Build 623
  Built under MSWin32
  Compiled at Dec 15 2000 16:27:07
  @INC:
    C:/Perl/lib
    C:/Perl/site/lib
    .

C:\>perl -MList::Util -e "print """Ok\n""";"
Can't locate List/Util.pm in @INC (@INC contains: C:/Perl/lib C:/Perl/
+site/lib .
).
BEGIN failed--compilation aborted.

C:\>
[download]



- Boldra

Yes, I see. It isn't your platform, it's the age of your perl installation. It appears that List::Util didn't make it into core until perl 5.7 and you're using 5.6 (and a very old version at that). You have my sympathies, but you really need to request that the version of perl should be upgraded. 5.10 just came out, and 5.8 has been available for ages...

To see when a module was added to core:

perl -MModule::CoreList -e "print Module::CoreList->first_release('Lis
+t::Util'), \"\n\""
[download]

This responds: 5.007003