because the OP doesn't want to clobber what's already in the hash. Assigning a list to a hash clears out the hash first, and then starts assigning the new values.

Update: argh, see mreece's reply to this post

Regardless, the map is completely redundant here, the following two are equivalent. 

%hash = map { split( /X/, $_ ) } ( "fooXbar","bishXbash");
%hash = split /X/, ("fooXbar","bishXbash");

[download]
---
my name's not Keith, and I'm not reasonable.

In reply to Re^2: Assign (key, value) to a hash w/o clobbering hash by reasonablekeith
in thread Assign (key, value) to a hash w/o clobbering hash by Melly

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