Joseph Ferano
dfd64d89ea
Copying a snippet into HTML is where a documented language stops being the real one. Each block on the page is a program here with its recorded output beside it, and check.sh is what says the page is still true after a change.
18 lines
508 B
Plaintext
18 lines
508 B
Plaintext
(defstruct Cursor
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[src [u8] ; a 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) (len (.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 "hi")})] ; pos omitted, so pos is 0
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(print-i64 (i64 (peek (addr c)))) (newline)
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(advance (addr c))
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(print-i64 (i64 (peek (addr c)))) (newline)))
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