Hacker News new | ask | show | jobs
by 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.
1 comments
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.
link
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.

link