oneOf package:megaparsec

oneOf ts succeeds if the current token is in the supplied collection of tokens ts. Returns the parsed token. Note that this parser cannot automatically generate the “expected” component of error message, so usually you should label it manually with label or (<?>).

oneOf cs = satisfy (`elem` cs)

See also: satisfy.

digit = oneOf ['0'..'9'] <?> "digit"

Performance note: prefer satisfy when you can because it's faster when you have only a couple of tokens to compare to:

quoteFast = satisfy (\x -> x == '\'' || x == '\"')
quoteSlow = oneOf "'\""

As the dual of oneOf, noneOf ts succeeds if the current token not in the supplied list of tokens ts. Returns the parsed character. Note that this parser cannot automatically generate the “expected” component of error message, so usually you should label it manually with label or (<?>).

noneOf cs = satisfy (`notElem` cs)

See also: satisfy. Performance note: prefer satisfy and anySingleBut when you can because it's faster.