If you're on a Unix/Linux/Mac, type perldoc perl into a terminal window, and see all the documentation you already have installed on your machine. ( I dunno how to view it on MSDos, but I'd try typing the same thing in a cmd shell. ) or you can go to CPAN or ask google to find 'perl pod'. perlsyn is the section which actually discusses syntax.

Briefly, there is almost never a reason to use the C style for loop. If you want to iterate over a list, let Perl handle the hard part:

for my $elem ( @$mysql ) {
    my $field1 = $elem->{field};
}

[download]

If you want to keep track of the index number, use the range operator, let Perl handle the hard part:

for my $idx ( 0..@$mysql ) {
    my $field1 = $mysql->[$idx]{field1};
}

[download]

Notes: If you specify an array in a scalar context, Perl decides you want to know how many elements there are in the array. The range operator is definitely a scalar context, it expects a number on the left and a number on the right. I frequently use scalar @array, so others will decipher what I'm doing more easily; some people think the superfluous 'scalar' is bad ( Hi Mike ).

Some people differentiate between 'for' and 'foreach'; they must love typing. I use 'for' for both, since Perl considers them synonyms.

You don't need to quote hash tags, you can use the bare text; similarly, the bare characters before a fat arrow are automatically taken as a string:

use 5.010;
$tag = 'Homer';
my %h = ( $tag => 'woohoo!', Fred => 'YABA DABA DOO!' );
say  Dumper(\%h);

# outputs:
# $VAR1 = {
#          'Homer' => 'woohoo!',
#          'Fred' => 'YABA DABA DOO!'
#        };

[download]

As Occam said: Entia non sunt multiplicanda praeter necessitatem.

In reply to Re: Style and Preference on Loops by TomDLux
in thread Style and Preference on Loops by Anonymous Monk

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