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Dear monks,

I would like to describe my problem with some sample codes below.

my %Hash; $Hash{'2012'}{'Jan'}{'13th'} = 1; # set 13th Jan 2012 to true $Hash{'2012'}{'Feb'}{'10th'} = 1; # set 10th Feb 2012 to true if ($Hash{'2013'}{'Oct'}{'11th'}{'1AM'}{'30Min'}) { # if so, do something } ## The if statement sets $Hash{'2013'}{'Oct'}{'11th'} to a hash ref ## which is undesirable. ## What I want is not to create $Hash{'2013'} at all. ## Later on if I check if ($Hash{'2013'}{'Oct'}{'11th'}) { ## I will end up here . . . ## I only want to be here if I set ## $Hash{'2013'}{'Oct'}{'11th'} = 1 explicitly. }

The problem is with the 'if ($Hash{'2013'}{'Oct'}{'11th'}{'1AM'}{'30Min'})' statement which creates $Hash{'2013'}{'Oct'}{'11th'}{'1AM'} as a hash ref. Is there any way to check the existence of a nested hash key without creating the parent hash keys? I can change the if statement to the one below but it looks clumsy . . .

if ($Hash{'2013'} && $Hash{'2013'}{'Oct'} && $Hash{'2013'}{'Oct'}{'11t +h'} && $Hash{'2013'}{'Oct'}{'11th'}{'1AM'} && $Hash{'2013'}{'Oct'}{'1 +1th'}{'1AM'}{'30Min'}) { # do something here }

In reply to Undesirable parent hash keys by sophate

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