I often see examples of straight values (excluding single & double quotes) as keys for hashes and most recenlty saw in Advanced Perl Programming, ex 2-3 (p 30) of 
$curr_prof->{Office Hours} = interval_parse($1);

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I receive an error when I try and test the code: Can't locate object method "Office" via package "Hours". At first I thought it must be an error that Sriram left out the quotes, but I could not find it in the errata I always use quotes or string variables as keys and will continue to do so, but is the above code an error or not? Further testing: 
$baseball_team{Seattle} = "Mariners";

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okay! 
$baseball_team{Los Angeles} = "Dodgers";

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error! 
$la = "Los Angeles";
$baseball_team{$la} = "Dodgers";

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okay!

In reply to using quotes in hash keys by thefid

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