Those examples are exactly equivalent. In general the only problem with these automatically quoted strings is that they need to be valid identifiers or integral numbers not starting with 0 (more or less matching /^([1-9]\d*)|([a-zA-Z_]\w*)$/).

update: as demonstrated by ikegami below, actually only valid identifiers are quoted: that means anything matching /^[a-zA-Z_]\w*$/ but not numbers.

As long as you use valid keys, and don't use version strings (/^v\d+$/) the quoted and unquoted keys are equivalent.

The version strings implementation makes $hash{v80} != $hash{'v80'} etc. in some versions of perl, so for portability these keys should always be quoted.

So, in short, if you don't want to think about the keys you use, quote them, but usually an intuitive key name can be used unquoted.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: Correct keys in hashes by Joost
in thread Correct keys in hashes by Scarborough

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