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I'm going to be more verbose.

You seem to be thinking that unary minus binds more tightly than exponentiation under normal arithmetic rules. It doesn't. You're expecting it to parse as

(-2)4 - 1

this is a misconception I've had to deal with often when tutoring community college students. By the normal precedence rules of arithmetic, it will actually be evaluated

-(24) - 1.

Perl (and most other programming languages) try to replicate the normal arithmetic precedence rules as closely as possible.

Remember, under normal arithmetic rules, exponentiation (the ** operator in Perl) binds more closely than multiplication (there's an implied multiplication in -2; it's shorthand for (-1) * 2), which binds more tightly than addition.


Information about American English usage here and here. Floating point issues? Please read this before posting. — emc


In reply to Re: ** operator in perl by swampyankee
in thread ** operator in perl by irah

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