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.
24 lines
814 B
Plaintext
24 lines
814 B
Plaintext
(defconst rows 3)
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(defconst cols 4)
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;; A fixed array is a value: inline storage, copies on assignment.
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(defconst palette [4 u32] [0xE6B800FF 0x3B6E8CFF 0xA83232FF 0xCC6B1FFF])
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;; No initialiser means all-bytes-zero, so this is BSS and costs nothing.
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(defvar grid [rows [cols i32]])
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(defn main []
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(set (at grid 1 2) 7)
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(print-i64 (i64 (at grid 1 2))) (newline) ; 7
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(print-i64 (i64 (len palette))) (newline) ; 4
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;; A slice is ptr+len and non-owning: it views the array, it does not copy it.
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(let [row (slice (at grid 1) 0 cols)]
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(set (at row 0) 5)
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(print-i64 (i64 (at grid 1 0))) (newline) ; 5 — the same storage
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(print-i64 (sum-i32 row)) (newline)) ; 12
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;; (zeroed) is a memset, not an allocation.
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(set grid (zeroed))
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(print-i64 (i64 (at grid 1 2))) (newline)) ; 0
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