What do you mean by "initialised"?

In your example, it seems the value is the empty string , which is defined. undef is undefined. To check for them, use

# empty string
defined $value && '' eq $value

# undefined
! defined $value

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Check for definedness is needed in the first case, as `undef` stringifies to the empty string.

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

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In reply to Re: Checking for blank string by choroba
in thread Checking for blank string by Himaja

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