[TUHS] > there is no way that FORTRAN can be described in any syntax

Ron Young rly1 at embarqmail.com
Tue Dec 4 06:55:23 AEST 2018

Your message dated: Mon, 03 Dec 2018 15:10:32 -0500
> On 12/3/18, Ron Young <rly1 at embarqmail.com> wrote:
> >
> >   John Levine wrote a ftn77 subset parser using lex and yacc (the shar
> >   file that I have is dated Nov 1988).
> >
> Just curious--what parts of Fortran 77 did he leave out?

	not sure... I'll check when I get home.
> Yes, full Fortran can be expressed in BNF and other formal syntax
> mechanisms.  But I don't think you can use lex and yacc to generate a
> compiler for it.

	agreed... but if you use Sale's classifier, you can insert
	whitespace to convert the input to something that lex/yacc can
	handle. Although in practice, using a hand-written lexer or
	a state machine (like open-watcom IIRC) would probably be the
        way to go.

> -Paul W.

Ron Young				rly1 at embarqmail.com

More information about the TUHS mailing list