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$Aoh{ testa } = @{ exec_select ($sql ) } [0] ->{ home1 };

This piece of code basically does the following

  • Execute exec_select with $sql as its argument (exec_select($sql))
  • Dereference its return value as an array ( @{ ... } )
  • Get the first element of this array ( @{ ... } [0] )
  • Dereference the array element as a hash ( ->{ ... } )
  • Get the key 'home1' from the dereferenced hash ( ->{ home1 } )
  • Assign the value stored in the hash with the key 'home1' to $Aoh{testa}
"Can't use an undefined value as a HASH reference..."

This error is caused by the first element in the above array being undefined. Therefor it can't be dereferenced as a hash.

Cheers, Flo


In reply to Re: Understanding this line of Code by rafl
in thread Understanding this line of Code by Anonymous Monk

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