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Re: EOF character in parser

Geert Bosch wrote:

The Ada front end always terminates files with an EOF character
after they have been read in. One of the advantages is that you
never need checking for end of file, you'll encounter it during
parsing. Note that, with a little care, this even works if
an EOF character may appear in other situations.

For example, when skipping white space, you can just increase
the scan pointer until it doesn't point to white space. No checks
for an out-of-range pointer are necessary.

Indeed, this technique is colloquially referred to as "Place a known elephant in Cairo".

--
Toon Moene - mailto:toon@moene.indiv.nluug.nl - phoneto: +31 346 214290
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GNU Fortran 95: http://gcc.gnu.org/fortran/ (under construction)

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