27 lines
765 B
OCaml
27 lines
765 B
OCaml
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(* Character operations *)
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external code: char -> int = "%identity"
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external unsafe_chr: int -> char = "%identity"
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let chr n =
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if n < 0 or n > 255 then invalid_arg "Char.chr" else unsafe_chr n
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external is_printable: char -> bool = "is_printable"
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let escaped = function
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'\'' -> "\\'"
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| '\\' -> "\\\\"
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| '\n' -> "\\n"
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| '\t' -> "\\t"
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| c -> if is_printable c then
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String.make 1 c
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else begin
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let n = code c in
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let s = String.create 4 in
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String.unsafe_set s 0 '\\';
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String.unsafe_set s 1 (unsafe_chr (48 + n / 100));
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String.unsafe_set s 2 (unsafe_chr (48 + (n / 10) mod 10));
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String.unsafe_set s 3 (unsafe_chr (48 + n mod 10));
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s
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end
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