...every construct that can be written with a goto can be written more clearly without one.

Try to rewrite TheDamian's Switch without the key goto $__; I dare you. Until you can do it, you haven't demonstrated that everything that can be written with a goto can be written without one (let alone written more clearly).

More generally read the thread at (Ovid) Re: Re (tilly) 2: Paradigm Shift - Don't use strict to find out my opinion on when it is justified.

The paper of Knuth's that was referred to there gives several other good reasons to use goto in at least some languages. Most of them boil down to the observation that there are many algorithms that can more efficiently be written with goto than without. At least in some languages.

But not in Perl. A theorem that Knuth refers to from the literature is that any flow of control that can be achieved with goto can be achieved with nested loops and named loop control. Therefore in Perl you need extraordinary reasons to really need goto. (TheDamian had an example that I believe to be exactly that extraordinary.)

Incidentally at Re: Re (tilly) 4: Paradigm Shift - when to use goto you will find a pre-processor macro from TheDamian showing you how to get named loops in C++. It uses goto, but considering that its purpose is to replace gotos that people write by hand with a more structured alternative, you may appreciate it.

UPDATE: I just checked. It seems that TheDamian renamed $__ at some point. He now has labels named "C_A_S_E_$casecounter" instead.

In reply to Re: Re: Re: block-based programming... by tilly
in thread block-based programming... by bronto

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