On Mon, Dec 13, 2010 at 1:05 AM, John W. Krahn <jwkr...@shaw.ca> wrote:
> shawn wilson wrote:
>>
>> i'm trying to exclude undefined variables for that are to be put into
>> a sql database date field, but none of this is working:
>>
>> sub correctdate { # make valid sql DATE field
>> my $date = $_[ 0 ];
>>
>> my ($month, $day, $year) = split / /, $date if defined( $date );
>
> That may not work correctly:
>
> perldoc perlsyn
> [ SNIP ]
> Statement Modifiers
> [ SNIP ]
> NOTE: The behaviour of a "my" statement modified with a
> statement modifier conditional or loop construct
> (e.g. "my $x if ...") is undefined. The value of the "my"
> variable may be "undef", any previously assigned value, or
> possibly anything else. Don't rely on it. Future versions of
> perl might do something different from the version of perl you
> try it out on. Here be dragons.
>
> You probably want something like:
>
> defined $date and my ( $month, $day, $year ) = split /[\s,]+/, $date;
>
>
>> $day =~ s/,//g if defined( $day );
>>
>> my %monnum = qw(
>> January 01 February 02 March 03 April 04 May 05
>> June 06 July 07 August 08 September 09 October 10
>> November 11 December 12
>> );
>>
>> if( $year&& $month&& $day ) {
>> my $corrected = "$year-$monnum{$month}-$day";
>> } else {
>> my $corrected = "0000-00-00";
>> }
>
> my() creates a variable that is only visible inside the scope of the {}
> braces. You probably want something like:
>
> my $corrected = $year && $month && $day
> ? "$year-$monnum{$month}-$day"
> : "0000-00-00";
>
>> return $corrected;
>> }
the above should work. thanks.
>
> Or perhaps you could do something like this:
>
> sub correctdate { # make valid sql DATE field
> my $date = $_[ 0 ];
>
> my %monnum = qw(
> January 1 February 2 March 3 April 4
> May 5 June 6 July 7 August 8
> September 9 October 10 November 11 December 12
> );
>
> my ( $month, $day, $year ) = defined $date
> ? map( $monnum{ $_ } || $_, split /[\s,]+/, $date )
> : ( 0, 0, 0 );
>
> return sprintf '%04d-%02d-%02d', $year, $month, $day;
> }
>
though that might work, it looks a bit complicated - i hate using a
ton of $_ - that code was a pain to understand... i'd use it if i
didn't have to maintain it :)
thanks for your help. i'll use the former first thing tomorrow.
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