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by david-given 3545 days ago
As I say, it's been years. I don't recall -> and ; at all. (Was there ever a time when they weren't in the language?) They look much nicer than cut and the implicit control flow.

I am, actually, right now struggling with priority-and-constraint-based register allocation and instruction selection for a compiler backend. It is so the right kind of problem for Prolog.
1 comments
talideon 3545 days ago
There's nothing funny about ';': it's just 'or'. Combined with '->', which means 'then', it essentially comes to behave like an 'else'.

';' has been in the language since the beginning, and I'm pretty sure '->' was too, but can't say for sure.

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tom_mellior 3545 days ago
I think -> is newer, but it's in ISO Prolog, which came out in 1995. So it's rather likely that the OP learned Prolog at a time when -> existed but teaching resources had not caught up. Not sure if that's the case even now.
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talideon 3545 days ago
I learned Prolog back in 1997, so it may have existed in the implementations I used back then. Must see if I can find an implementation of HU Prolog from back then. I also used SWI Prolog from back then, and I'd expect that was more up to date.

Edit: mention SWI Prolog.

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