Nyet. If you want log() then you'll need $opts{+log}, just like normal. The default idea is for a hash key to be a string, so it's the log() not the 'log' that needs clarification. Note that $opts{log(5)} isn't ambiguous, only the implicit illegal log of 0 that you get without giving it an argument.

(I'd love to see the code that uses the log of zero for a hash key...)
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