Ouch!. That creates 5 unneccesary temporary lists and an unneccesary temporary array:

#T1  L2             L1      
@a = grep { /cat/ } keys %h1
#  L5    L4  L3
@b{@a} = @h1{@a}

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In reply to Re^2: Is there a simple syntax to logically slice a hash? by BrowserUk
in thread Is there a simple syntax to logically slice a hash? by misterperl

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