Returns true if this points to the start of the paragraph delimiter characters for a line (delimiters will be either a newline, a carriage return, a carriage return followed by a newline, or a Unicode paragraph separator character).
Note that an iterator pointing to the \n of a \r\n pair will not be counted as the end of a line, the line ends before the \r. The end iterator is considered to be at the end of a line, even though there are no paragraph delimiter chars there.
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an iterator |
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whether this is at the end of a line |