38 lines
702 B
OCaml
38 lines
702 B
OCaml
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type t =
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| Int of int
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| Ident of string
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| Plus
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| Minus
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| Asterisk
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| Slash
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| LParen
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| RParen
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let of_char = function
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| '+' -> Plus
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| '-' -> Minus
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| '*' -> Asterisk
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| '/' -> Slash
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| '(' -> LParen
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| ')' -> RParen
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| _ -> invalid_arg "Token.of_char"
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let of_string str =
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let fc = Char.code str.[0] in
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if Char.(code '0' <= fc && fc <= code '9') then
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Int (int_of_string str)
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else
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match str with
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| _ when String.length str = 1 -> of_char str.[0]
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| _ -> failwith "Token.of_string"
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let to_string = function
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| Int n -> string_of_int n
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| Ident s -> s
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| Plus -> "+"
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| Minus -> "-"
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| Asterisk -> "*"
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| Slash -> "/"
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| LParen -> "("
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| RParen -> ")"
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