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Comment by horsh1 | Hacker News Reader

Less repetitions. Instead of

   roo(X, W) :- zut(X, Z), pum(Z, Y), tos(Y, W)

we could write something like

   roo/2 :- zut . pum . tos

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You can do this with definite clause grammars (DCGs), which are available in virtually all Prolog systems:

    roo --> zut, pum, tos.

Note the use of (-->)/2 to define a grammar rule. Use phrase/3 to invoke the DCG. DCGs are currently being drafted for inclusion in the Prolog ISO standard:

https://www.complang.tuwien.ac.at/ulrich/iso-prolog/#dcg

Yea, that's a good thing.

And also there are user defined functions on dicts. Those are all moves in the right direction, but all seem ad hoc and partial.

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