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Show HN: Prolog compiler and interpreter in pure JavaScript

• colanderman 11y ago
  ?- X = 10. X = _ no. ...this doesn't work like any Prolog I know. (Even defining equality manually as "eq(X, X)." doesn't work...)
  • dmytrish 11y ago
    Why? `?-` indicates that it's a query, it should not define anything.
    • colanderman 11y ago
      $ swipl ?- X = 10. X = 10. $ gprolog | ?- X = 10. X = 10 yes (a) The REPL should print the variable bindings which caused the query to succeed. (b) The query `X = 10.` should succeed trivially. I've been using Prolog on-and-off for close to a decade now and have implemented my own pseudo-Prolog (also in Javascript; was missing logic variables and extra-logical builtins). I tried to get pretty much any query to succeed in this interpreter and couldn't. This is not any kind of Prolog that I'm familiar with.
      • dmytrish 11y ago
        Yep, I agree I was wrong (having too little experience in Prolog): variables are necessary to extract values from queries.