18 lines
520 B
Plaintext
18 lines
520 B
Plaintext
(defstruct Cursor
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[src [const u8] ; a read-only, non-owning slice
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pos i32]) ; no initialiser means zeroed
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(defn peek [c (Ptr Cursor)] u8
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(if (< (.pos c) (length (.src c)))
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(at (.src c) (.pos c))
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0))
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(defn advance [c (Ptr Cursor)] ()
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(set (.pos c) (+ (.pos c) 1))) ; field access derefs one level
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(defn main [] ()
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(let [c (Cursor {.src (bytes-view "hi")})] ; pos omitted, so pos is 0
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(print (peek (addr c))) (println "")
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(advance (addr c))
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(print (peek (addr c))) (println "")))
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