comment on

The use version creates a tied perl hash, employing caching ... while the other version doesn't bother to do that and simply matches on a scalar.

perl -d:Trace -V:ccflags
>> Config.pm:1012:     foreach(@_){
>> Config.pm:1013:  config_re($_), next if /\W/;
>> Config.pm:1014:  my $v=(exists $Config{$_}) ? $Config{$_} : 'UNKNOW
+N';
>> Config.pm:988:     exists($_[0]->{$_[1]}) or
>> Config.pm:882:     return $_[0]->{$_[1]} if (exists $_[0]->{$_[1]})
+;
>> Config.pm:885:     my($value, $start, $marker, $quote_type);
>> Config.pm:887:     $quote_type = "'";
>> Config.pm:889:     if ($_[1] eq 'byteorder') {
>> Config.pm:929:   $marker = "$_[1]=";
>> Config.pm:932:   $start = index($config_sh, "\n$marker$quote_type")
+;
>> Config.pm:934:   if ($start == -1) {
>> Config.pm:938:   return undef if ( ($start == -1) &&  # in case it'
+s first
>> Config.pm:940:   if ($start == -1) {
>> Config.pm:947:       $start += length($marker) + 2;
>> Config.pm:949:   $value = substr($config_sh, $start,
>> Config.pm:956:     if ($quote_type eq '"') {
>> Config.pm:963:     $value = undef if $value eq 'undef';
>> Config.pm:964:     $_[0]->{$_[1]} = $value; # cache it
>> Config.pm:965:     return $value;
>> Config.pm:1015:  $v='undef' unless defined $v;
>> Config.pm:1016:  print "$_='$v';\n";
ccflags='-nologo -O1 -MD -DNDEBUG -DWIN32 -D_CONSOLE -DNO_STRICT -DHAV
+E_DES_FCRYPT  -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -D
PERL_MSVCRT_READFIX';
>> Config.pm:1012:     foreach(@_){
[download]

Maybe i'm wrong ...

In reply to Re: Re: •Re: Check whether your hash keys have random order by Anonymous Monk
in thread Check whether your hash keys have random order by liz

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