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21 lines
479 B
Racket
21 lines
479 B
Racket
9 years ago
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#lang ragg
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;; use uppercase TOKEN-IDENTIFIERS for classes of tokens
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;; too numerous to indicate individually
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;; (e.g., numbers, strings)
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bf-program : (op | loop)*
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op : ">" | "<" | "+" | "-" | "." | ","
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loop : "[" (op | loop)* "]"
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;; Alternate ways of specifying grammar
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;; bf-program : op*
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;; op : ">" | "<" | "+" | "-" | "." | "," | loop
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;; loop : "[" op* "]"
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;; bf-program : expr*
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;; expr : op | loop
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;; op : ">" | "<" | "+" | "-" | "." | ","
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;; loop : "[" bf-program "]"
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