Function nom::alpha

pub fn alpha<T>(input: T) -> IResult<T, T, u32> where
    T: Slice<Range<usize>> + Slice<RangeFrom<usize>> + Slice<RangeTo<usize>>,
    T: InputIter + InputLength + AtEof,
    <T as InputIter>::Item: AsChar,
    <T as InputIter>::RawItem: AsChar, 

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