55 lines
1.0 KiB
Plaintext
55 lines
1.0 KiB
Plaintext
# A tree walk interpreter for ludus
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(var interpret nil)
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(defn- iff [ast ctx]
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(def [condition then else] (ast :data))
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(if (interpret condition ctx)
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(interpret then ctx)
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(interpret else ctx)))
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(defn- script [ast ctx]
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(print "interpreting script")
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(def lines (ast :data))
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(var result nil)
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(each line lines
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(print "interpreting script line")
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(set result (interpret line ctx)))
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result)
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(defn- interpret* [ast ctx]
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(print "interpreting ast node " (ast :type))
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(case (ast :type)
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:nil nil
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:number (ast :data)
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:bool (ast :data)
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:string (ast :data)
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:keyword (ast :data)
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:if (iff ast ctx)
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:script (script ast ctx)))
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(set interpret interpret*)
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# repl
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(try (os/cd "janet") ([_] nil))
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(import ./scanner :as s)
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(import ./parser :as p)
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(import ./validate :as v)
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(var source nil)
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(defn run []
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(def scanned (s/scan source))
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(def parsed (p/parse scanned))
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(def validated (v/valid parsed))
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(pp parsed)
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(interpret (parsed :ast) @{}))
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(do
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(set source `
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if false then :bar else :baz
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`)
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(run)
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)
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