On 7/7/20 05:35, Akim Demaille wrote:
I believe you need to read again the documentation of /
'r/s'
It is not as simple as that. As I don't speak BASIC, let me rephrase
this problem in FORTRAN IV which is also "blank agnostic":
DO <number> <variable> = <expression> , <expression> [, <expression>]
It is not until you reach the comma after the first expression that you
know whether the statement is the beginning of a loop or it is an
assignment. And the expression can contain commas in function calls,
which defeats any trivial lookahead scanning. E.g.,
D O 17 6PQ R=FUN X(1 4, V 8)
is an assignment to variable DO176PQR. The function arguments can also
be expressions that contain function calls.
As you can see, this more or less defeats any attempt to write a lex
scanner. And you cannot just squeeze out all blanks in a front end
because "Hollerith fields" can contain blanks that are significant (must
remain).
