mirror of https://github.com/lark-parser/lark.git
43 lines
932 B
Python
43 lines
932 B
Python
#
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# This example demonstrates lex-less parsing using the earley_nolex frontend
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#
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# Using a lexer for configuration files is tricky, because values don't
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# have to be surrounded by delimiters.
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# In this example with skip lexing and let the Earley parser resolve the ambiguity.
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#
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# Future versions of lark will make it easier to write these kinds of grammars.
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#
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from lark import Lark, Transformer
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parser = Lark(r"""
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start: _nl? section+
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section: "[" name "]" _nl item+
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item: name "=" value _nl
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name: /[a-zA-Z_]/ /\w/*
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value: /./+
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_nl: (_CR? _LF)+
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_CR : /\r/
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_LF : /\n/
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""", parser="earley_nolex")
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class RestoreTokens(Transformer):
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value = ''.join
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name = ''.join
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def test():
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sample_conf = """
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[bla]
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a=Hello
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this="that",4
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"""
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r = parser.parse(sample_conf)
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print(RestoreTokens().transform(r).pretty())
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if __name__ == '__main__':
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test()
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