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in reply to Re: disadvantages of perl
in thread disadvantages of perl

# WTF if ( defined $r && ref $r && ref $r eq 'HASH' && keys %$r ) { ... }
indeed
if( $r and UNIVERSAL::isa($r,'HASH') and %$r ) { ... }
Exposed internals. I know about the guts. I'd like to not care. KTHX. ..

You don't need to know about the guts, but you do need to encode your data, if you care about its encoding.

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Re^3: disadvantages of perl
by ikegami (Patriarch) on Jul 02, 2009 at 15:52 UTC

    You don't need to know about the guts, but you do need to encode your data, if you care about its encoding.

    Unfortunately, you do in some circumstances. For example, the only difference in between $up and $dn in the following is the internal storage format, yet they differ in output.

    $\ = "\n"; utf8::downgrade $dn = chr(0xC9); utf8::upgrade $up = chr(0xC9); # <5.10 >=5.10 print pack('A', $dn) eq chr(0xC9) ?1:0; # 1 1 print pack('A', $up) eq chr(0xC9) ?1:0; # 0 1 print $dn =~ /\w/ ?1:0; # 0 print $up =~ /\w/ ?1:0; # 1

    They are being fixed. As you can see, pack no longer depends on the internal encoding since 5.10.0. Other discrepencies such as /\w/ are being fixed too.

Re^3: disadvantages of perl
by Anonymous Monk on Jul 02, 2009 at 14:36 UTC
    Should be
    if( UNIVERSAL::isa($r,'HASH') and %$r ) { ... }

      ... except that even that abusive code can't accurately determine if you can dereference all hashlike $r as a hash.