Converts from a pointer to position within a string to an integer character offset.
Since 2.10, this function allows @pos to be before @str, and returns a negative offset in this case.
a UTF-8 encoded string
a pointer to a position within @str
the resulting character offset
See Implementation
Converts from a pointer to position within a string to an integer character offset.
Since 2.10, this function allows @pos to be before @str, and returns a negative offset in this case.