Hints
#####

Some additional hints for your edification.

Author: Matthias Urlichs <smurf@debian.org>

How to process C preprocessor codes:
====================================

Rudimentary include handling has been added to the parser by me.

However, if you want to do anything fancy, like for instance whatever
the C preprocessor does, things get more complicated. Fortunately,
there's already a nice tool to handle C preprocessing -- CPP itself.

If you want to report errors correctly in that situation, do this:

	def set_line(s,m):
		"""Fixup the scanner's idea of the current line"""
		s.filename = m.group(2)
		line = int(m.group(1))
		s.del_line = line - s.line

	%%
	parser whatever:
		ignore:    '^#\s*(\d+)\s*"([^"\n]+)"\s*\n' {{ set_line }}
		ignore:    '^#.*\n'

	[...]
	%%
	if __name__=='__main__':
		import sys,os
		for a in sys.argv[1:]:
			f=os.popen("cpp "+repr(a),"r")

			P = whatever(whateverScanner("", filename=a, file=f))
			try: P.goal()
			except runtime.SyntaxError as e:
				runtime.print_error(e, P._scanner)
				sys.exit(1)

			f.close()

