make RegexParser.err handle whitespace like literal and regex. #30
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This overrides `err` in RegexParser to make it consume whitespace just
like regex and literal. The original motivation was:
object parser extends RegexParsers {
def num = "\\d+".r
def twoNums = num ~ (num | err("error!"))
}
// succeeds
parser.parseAll(twoNums, "42 721")
// fails with a parsing Failure instead of an Error
// because err doesn't consume the whitespace but the regex does.
parser.parseAll(twoNums, "42 foo")
This may change the output of some parsers that failed to parse input
(from a Failure to an Error).
Fixes scala#29
|
I am still not 100% convinced that this change cannot break somebody's parser, by turning a successful parse into an error (because of no backtracking with errors compared to failures)... |
|
... but even if that's a semantic change, it is worth it. |
gourlaysama
added a commit
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Aug 18, 2014
make RegexParser.err handle whitespace like literal and regex.
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This overrides
errin RegexParser to make it consume whitespace justlike regex and literal. The original motivation was:
This may change the output of some parsers that failed to parse input
(from a Failure to an Error).
Fixes #29