Obtains an iterator pointing to char_offset within the given line. Note characters, not bytes; UTF-8 may encode one character as multiple bytes.

Before the 3.20 version, it was not allowed to pass an invalid location.

Since the 3.20 version, if line_number is greater than the number of lines in the buffer, the end iterator is returned. And if char_offset is off the end of the line, the iterator at the end of the line is returned.

class TextBuffer


iter TextIter

iterator to initialize

lineNumber int

line number counting from 0

charOffset int

char offset from start of line