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whitespacepyparsing

pyparsing: match words on same line

In pyparsing I'm looking for a simple way to match words (or other expressions) that occur on the same line, i.e. without any newline in between them.

Solution

  • You can override the default whitespace-skipping characters for a particular parser element - in this case, the word_on_the_same_line only skips spaces, but not newlines.

    import pyparsing as pp

word = pp.Word(pp.alphas, pp.alphanums)

# define special whitespace skipping, so that newlines aren't 
# skipped when matching a word_on_the_same_line
word_on_the_same_line = word().setWhitespaceChars(" ")

# compare results with this version of word_on_the_same_line to see 
# how pyparsing treats newlines as skippable whitespace
# word_on_the_same_line = word()

line = pp.Group(word("key") + word_on_the_same_line[...]("values"))

test = """\
key1 lsdkjf lskdjf lskjdf sldkjf
key2 sdlkjf lskdj lkjss lsdj
"""

print(line[...].parseString(test).dump())

    Prints:

    [['key1', 'lsdkjf', 'lskdjf', 'lskjdf', 'sldkjf'], ['key2', 'sdlkjf', 'lskdj', 'lkjss', 'lsdj']]
[0]:
  ['key1', 'lsdkjf', 'lskdjf', 'lskjdf', 'sldkjf']
  - key: 'key1'
  - values: ['lsdkjf', 'lskdjf', 'lskjdf', 'sldkjf']
[1]:
  ['key2', 'sdlkjf', 'lskdj', 'lkjss', 'lsdj']
  - key: 'key2'
  - values: ['sdlkjf', 'lskdj', 'lkjss', 'lsdj']