27 lines
626 B
Standard ML
27 lines
626 B
Standard ML
(* The shallow abstract syntax *)
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type location =
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Location of int * int
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type regular_expression =
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Epsilon
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| Characters of char list
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| Sequence of regular_expression * regular_expression
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| Alternative of regular_expression * regular_expression
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| Repetition of regular_expression
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type lexer_definition =
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Lexdef of location * (string * (regular_expression * location) list) list
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(* Representation of automata *)
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type automata =
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Perform of int
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| Shift of automata_trans * automata_move array
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and automata_trans =
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No_remember
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| Remember of int
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and automata_move =
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Backtrack
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| Goto of int
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