It has nothing to do with danger. It's a parsing/tokenizer thing. An unquoted string that looks like an identifier is a single token. The next token is the curly brace - so with one lookahead token, perl can determine it's a bareword that needs autoquoting. But if it sees a comma, it doesn't know what's happening - it cannot say "hmmm, I saw an opening curly brace, a bare word, a comma, perhaps it's a list, let's just see if it's a list of bare words all the way until the closing brace, if something else happens, I just backpaddle and try something else".

If you do want perl to parse $hash{key1,key2,key3}, just turn off use strict 'subs'.

In reply to Re: Unquoted hash slice keys with use strict 'subs' by JavaFan
in thread Unquoted hash slice keys with use strict 'subs' by cdarke

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