54 lines
1.0 KiB
Markdown
54 lines
1.0 KiB
Markdown
# rusty-wam
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The beginnings of the Warren Abstract Machine in Rust, according to
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the progression of languages in [Warren's Abstract Machine: A Tutorial
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Reconstruction](http://wambook.sourceforge.net/wambook.pdf), ending in
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pure Prolog.
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## Progress
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The language L0 is implemented as a simple REPL. It supports
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unification on facts and queries without backtracking and rules
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without clauses, in the familiar Prolog syntax. No data types apart
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from atoms are currently supported.
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An example of the level of interaction currently supported is:
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```
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l0> p(Z, Z).
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Program stored.
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l0> ?- p(Z, Z).
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yes
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l0> ?- p(Z, z).
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yes
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l0> ?- p(Z, w).
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yes
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l0> ?- p(z, w).
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no
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l0> ?- p(w, w).
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yes
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l0> ?- p(Z, h(Z, W), f(W)).
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no
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l0> p(Z, h(Z, W), f(W)).
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Program stored.
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l0> ?- p(z, h(z, z), f(w)).
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no
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l0> ?- p(z, h(z, w), f(w)).
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yes
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l0> ?- p(Z, h(z, W), f(w)).
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yes
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l0> ?- p(z, h(Z, w), f(w)).
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yes
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l0> quit
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```
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## Occurs check
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There's no occurs check, so cyclic terms do unify:
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```
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l0> p(W, W).
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Program stored.
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l0> ?- p(f(f(W)), W).
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yes
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``` |