Instead of non-working '+' or offending '()', you could use '&' (only one character long and in the same place as '+' would have been if it worked).

Note also in perldoc (perl 5.8.8) ...

Unary "+" has no effect whatsoever, even on strings. It is useful syntactically for separating a function name from a parenthesized expression that would otherwise be interpreted as the complete list of function arguments. (See examples above under "Terms and List Operators (Leftward)".)

How about using Readonly already?

Later ... one more way to make a constant (sub) behave: $p = { (P) => 1 } where P is a constant (sub).

In reply to Re: On quoting the lhs of '=>' by parv
in thread On quoting the lhs of '=>' by rovf

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