49 lines
1.3 KiB
Python
49 lines
1.3 KiB
Python
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from string import ascii_letters, digits
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from rply import LexerGenerator
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VALID_CHARACTERS = ascii_letters[:3]+ascii_letters[4:]+"_"+digits
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TOKENS = [
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("ROLL_DIE", r"d"),
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("ROLL_KEEP_HIGHEST", r"kh"),
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("ROLL_KEEP_LOWEST", r"kl"),
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("ROLL_MIN", r"min"),
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("ROLL_MAX", r"max"),
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("ROLL_EXPLODE", r"!"),
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("SYMBOL_LE", r"\<\="),
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# ("SYMBOL_GE", r"\>\="),
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("SYMBOL_EQUALS", r"\="),
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("SYMBOL_ARROW", r"\-\>"),
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("SYMBOL_BACKSLASH", r"\\"),
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("SYMBOL_LPARENS", r"\("),
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("SYMBOL_RPARENS", r"\)"),
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("SYMBOL_PLUS", r"\+"),
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("SYMBOL_MINUS", r"\-"),
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("SYMBOL_TIMES", r"\*"),
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("SYMBOL_DIVIDE", r"\/"),
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("KEYWORD_LET", r"let"),
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("KEYWORD_IN", r"in"),
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("KEYWORD_IF", r"if"),
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("KEYWORD_THEN", r"then"),
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("KEYWORD_ELSE", r"else"),
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("INT", r"\d+"),
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("ID", f"[{ascii_letters}][{VALID_CHARACTERS}]*")
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]
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class Lexer():
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def __init__(self):
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self.lexer = LexerGenerator()
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def _add_tokens(self):
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for token in TOKENS:
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self.lexer.add(*token)
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self.lexer.ignore(r"\s+")
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def get_lexer(self):
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self._add_tokens()
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return self.lexer.build()
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