Re: [Pyparsing] setResultsName on a recursive element of grammar

[Elizabeth M. <eli...@in...>]

On 20/02/16 10:36, Paul McGuire wrote:
> Here is the whole parser in one copy/pasteable chunk:
> 
>     command = Word(alphas) | Word(nums)
>     COLON = Suppress(':')
>     middle = ~COLON + Word(printables)
>     trailing = Word(printables)
>     params = (OneOrMore(middle)("middle") + 
>               COLON + 
>               ZeroOrMore(trailing)("trailing"))
>     line = (command("command") + Group(params)("params"))
> 
>     tests = """\
>         COMMAND param1 param2 : param3"""
>     line.runTests(tests)
> 
> And no need to kludge in any `listAllMatches` behavior either.
> 
> -- Paul
> 
> 
> 
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There was one minor thing I forgot. Word(printables) is insufficient in
your example, as any 8-bit string is acceptable in parameters (and are
often used).

The encoding is not specified for these portions (deliberately it
seems), but I usually implicitly assume UTF-8, since that is the
de-facto standard. As such, UTF-8 is what I decode all stuff from the
wire to, using the 'replace' error handler.

This is my proposed solution to match all characters but surely there is
a better way than the below (perhaps using Regex is better?):

    # 1111998 is the total number of valid Unicode characters.
    utf8_chars = ''.join(chr(x) for x in range(1111998))
    middle = (~COLON + ~White()) + Word(utf8_chars)

--
Elizabeth