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in reply to Should chomping a constant always raise an error?

In a language as dynamic as Perl, we cannot have a lot of compile-time checks, and I am always happy when it happens, as in this case. I commend the compiler for complaining!

Obviously, it doesn't make much sense to chomp a constant, but if your operating within a sub, you don't know what the user will pass you.

I do not quite understand this. Inside of a sub, when the user passes in some data, it would not be a constant, would it?

If the user passes a constant that doesn't need chomping it would be nice to allow that thtough without having to duplicate the tests inherent in chomp?

What exactly do you mean by constant? I take it to be something that is known at compile-time.

I think it would be nice if the compiler optimized away the chomp completely if called with a compile-time constant. But I am not sure this is a feature many people need.

Update: After reading BigLug's response and his excellent examples, I now understand what you meant by "inside of a sub". In this case, I tend to agree with you, that the run-time error that occurs when you pass in a read-only 'fred' (which does not need to be modified) is a little harsh. On the other hand, the subroutine modify wants to modify its parameter and passing constants to it would be as illegal as passing them directly to chomp.