Re: Software maintenance

On Sun, 19 Sep 2010 22:20:39 +0200, jacob navia wrote:

Comments do not affect program behavior. Line splicing is done after
comment processing.

Isn't that a very simple rule?

I suspect only for those who do translation phase 3 before phase 2.

This "translations phases" model is wrong. Lines can be put together
only after the comments have been stripped out

Which means that you can't split comments; which means that you have to be
able to recognise comments if you want to split lines.

The benefit of line-splicing being done at such an early stage is that you
can take a 132-column source file and convert it to an equivalent
80-column source file with little more than a one-line sed script (the
only gotcha is that you can't insert a backslash-newline into the middle
of a trigraph). Using trigraphs to convert a US-ASCII source file to one
using the ISO-646 invariant subset is similarly straightforward.

Essentially, the first two phases deal with file encoding issues, not
language issues per se. In the same way that the first six phases can
easily be moved into a separate pre-processor (and often are), the first
two phases could be moved into a pre-pre-processor.

.