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perl explain syntax !!!

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# 1  
Old 05-08-2009
perl explain syntax !!!
hi all
i was going through some perl code i came across this line and i am not getting what is exactly going on ..

Code:
$$this{localtion} = GetName->GetVarName("EXE_DIR") ;

what is the red part doing in above code
# 2  
Old 05-08-2009
From the hash 'this', get the value associated with the key 'localtion', and treat it as a reference to a scalar.
# 3  
Old 05-12-2009
Quote:
Originally Posted by pludi
From the hash 'this', get the value associated with the key 'localtion', and treat it as a reference to a scalar.
This is not really correct.

$this is a hash reference. That is, a reference to a hash. $$this{'location'} dereferences $this to access the value associated with the "location" key.

Another way to write this is $this->{'location'} = 'xxxxxxx';

You may easily confirm this by using Data::Dumper to inspect complex data structure.

Code:
C:\Users\bernardchan>perl -MData::Dumper -e "$$this{'location'}='xxxx'; print Dumper($this)"
$VAR1 = {
          'location' => 'xxxx'
        };

C:\Users\bernardchan>perl -MData::Dumper -e "$this->{'location'}='xxxx'; print Dumper($this)"
$VAR1 = {
          'location' => 'xxxx'
        };

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