If a user wishes to input an argument that contains a blank, comma,
comment character, special delimiter, etc., then the argument should begin
with the begin quote (``) character, and have an end quote (") character at the end.
Reaching the end of the input line is equivalent to having
the end quote character. If you want to have the string include the
end quote character, then you should double the character (similar
to the way that FORTRAN handles character strings with embedded single
quotes). By default, the begin quote and end quote characters are
the same (the ASCII double-quote: " ), although a particular
program that uses XPARSE is allowed to change these (and all special
characters) to different characters. For example:
"This argument contains blanks" "This argument ends with a single """," followed by a 2nd argument" "The initial "" allow the words following the ! to be read" " A final "" is optional for the last argument