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From: RedGrittyBrick on 29 Mar 2010 18:00 Dr.Ruud wrote: > RedGrittyBrick wrote: > >> my $query = new CGI; > > ITYM: > > my $cgi = CGI::->new(); > Yes, I did hesitate over that. In the end I copied what is in the documentation http://perldoc.perl.org/CGI.html#PROGRAMMING-STYLE. I've actually forgotten the pitfalls of the, er, deprecated syntax. Perusing perlobj, perlboot and perltoot didn't help me (though I wasn't very thorough). Is it anything to do with naming your constructor shazam and writing `my $instance = shazam OddObject'. Though it works, presumably as intended, I guess that sort of thing can confuse people & perl? So, why is `CGI::->new()' preferred over `CGI->new()' preferred over `new CGI()'? -- RGB
From: Dr.Ruud on 29 Mar 2010 18:23 RedGrittyBrick wrote: > Dr.Ruud wrote: >> RedGrittyBrick wrote: >>> my $query = new CGI; >> >> ITYM: >> >> my $cgi = CGI::->new(); >> > > Yes, I did hesitate over that. In the end I copied what is in the > documentation http://perldoc.perl.org/CGI.html#PROGRAMMING-STYLE. > > I've actually forgotten the pitfalls of the, er, deprecated syntax. > Perusing perlobj, perlboot and perltoot didn't help me (though I wasn't > very thorough). Is it anything to do with naming your constructor shazam > and writing `my $instance = shazam OddObject'. Though it works, > presumably as intended, I guess that sort of thing can confuse people & > perl? > > So, why is `CGI::->new()' preferred over `CGI->new()' preferred over > `new CGI()'? perl -MData::Dumper -MCGI -wle' sub new { die "in new" } sub CGI { die "in CGI" } my $cgi = CGI::->new; print Dumper $cgi; ' $VAR1 = bless( { '.parameters' => [], '.charset' => 'ISO-8859-1', '.fieldnames' => {}, 'escape' => 1 }, 'CGI' ); -- Ruud
From: sreservoir on 29 Mar 2010 18:32 On 3/29/2010 6:00 PM, RedGrittyBrick wrote: > Dr.Ruud wrote: >> RedGrittyBrick wrote: >> >>> my $query = new CGI; >> >> ITYM: >> >> my $cgi = CGI::->new(); >> > > Yes, I did hesitate over that. In the end I copied what is in the > documentation http://perldoc.perl.org/CGI.html#PROGRAMMING-STYLE. > > I've actually forgotten the pitfalls of the, er, deprecated syntax. > Perusing perlobj, perlboot and perltoot didn't help me (though I wasn't > very thorough). Is it anything to do with naming your constructor shazam > and writing `my $instance = shazam OddObject'. Though it works, > presumably as intended, I guess that sort of thing can confuse people & > perl? > > So, why is `CGI::->new()' preferred over `CGI->new()' preferred over > `new CGI()'? it isn't, unless someone's stupid enough to make &new or &CGI. it's just less ambiguous: new CGI chokes if there is a &new or a &CGI. CGI->new chokes if there is a &CGI. might do bad things if CGI isn't require'd or use'd. 'CGI'->new almost always does the right thing. CGI::->new is syntactic sugar for 'CGI'->new. actally, foo::bar:: is syntactic sugar for 'foo::bar' except in one specific case, which usually shouldn't come up. I use it in tie, mostly. -- "Six by nine. Forty two." "That's it. That's all there is." "I always thought something was fundamentally wrong with the universe."
From: sreservoir on 29 Mar 2010 18:33 On 3/29/2010 6:23 PM, Dr.Ruud wrote: > RedGrittyBrick wrote: >> Dr.Ruud wrote: >>> RedGrittyBrick wrote: > >>>> my $query = new CGI; >>> >>> ITYM: >>> >>> my $cgi = CGI::->new(); >>> >> >> Yes, I did hesitate over that. In the end I copied what is in the >> documentation http://perldoc.perl.org/CGI.html#PROGRAMMING-STYLE. >> >> I've actually forgotten the pitfalls of the, er, deprecated syntax. >> Perusing perlobj, perlboot and perltoot didn't help me (though I >> wasn't very thorough). Is it anything to do with naming your >> constructor shazam and writing `my $instance = shazam OddObject'. >> Though it works, presumably as intended, I guess that sort of thing >> can confuse people & perl? >> >> So, why is `CGI::->new()' preferred over `CGI->new()' preferred over >> `new CGI()'? > > perl -MData::Dumper -MCGI -wle' > sub new { die "in new" } > sub CGI { die "in CGI" } > my $cgi = CGI::->new; > print Dumper $cgi; > ' > > $VAR1 = bless( { > '.parameters' => [], > '.charset' => 'ISO-8859-1', > '.fieldnames' => {}, > 'escape' => 1 > }, 'CGI' ); this is horribly contrived and should never happen. but yes, this is a case where ::-> is preferred. -- "Six by nine. Forty two." "That's it. That's all there is." "I always thought something was fundamentally wrong with the universe."
From: Ben Morrow on 29 Mar 2010 22:19
Quoth sreservoir <sreservoir(a)gmail.com>: > On 3/29/2010 6:23 PM, Dr.Ruud wrote: > > > > perl -MData::Dumper -MCGI -wle' > > sub new { die "in new" } > > sub CGI { die "in CGI" } > > my $cgi = CGI::->new; > > print Dumper $cgi; > > ' > > > > $VAR1 = bless( { > > '.parameters' => [], > > '.charset' => 'ISO-8859-1', > > '.fieldnames' => {}, > > 'escape' => 1 > > }, 'CGI' ); > > this is horribly contrived and should never happen. but yes, this is > a case where ::-> is preferred. perldoc aliased. Ben |