Read the error message once more: the argument of exist cannot be an array. @{$pop{$element}{interactions}} is an array.

If you want to check the whole array, use the any function fom List::MoreUtils.

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

My blog: Imperial Deltronics

In reply to Re: searching for elements by CountZero
in thread searching for elements by Anonymous Monk

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