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Show HN: Term-Lisp – A Lisp, based on pattern matching and term rewriting

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58 points boris_m | 1 comments | 06 Nov 24 14:53 UTC | HN request time: 0.212s | source
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llm_trw ◴[06 Nov 24 18:20 UTC] No.42066742[source]▶
This is vastly more pattern matching than term rewriting. In a term rewriting system you have no types for a start: https://en.wikipedia.org/wiki/Rewriting
replies(1): >>42067012 #
convolvatron ◴[06 Nov 24 18:33 UTC] No.42067012[source]▶
is that important here? it looks like semantically types as presented are no more than magic constants to match on
replies(1): >>42067135 #
llm_trw ◴[06 Nov 24 18:41 UTC] No.42067135[source]▶
Yes, in term rewriting systems the only thing that matters is the lexical structure of the "program" you're running on top of the transform rules. A simple example of running a TRS is a term of a BNF grammar, a less simple one is a symbolically expanding a term in a computer algebra system.
replies(1): >>42067605 #
convolvatron ◴[06 Nov 24 19:09 UTC] No.42067605[source]▶
ok. sorry, so the issue is not that some of the runtime data is being interpreted as types, its that decisions are being made based on the data and not solely on the structure of the program.
replies(1): >>42073047 #
1. llm_trw ◴[07 Nov 24 03:25 UTC] No.42073047[source]▶
In the most general sense yes. However you can encode whatever you want on top of a trs, just like how you can encode any computer language in lambda calculus because both are Turing complete models of computation.