[seqfan] Program syntax and the OEIS

[Charles Greathouse]

The recent case of A006506 (where a correct program in Maple 5 no
longer gave correct answers in Maple 6+) has made me think about ways
to store information on programming language and version into the
program, maple, and mathematica fields.  (One day, perhaps, simple
conversion could be done between versions, but in the medium term this
would at least alert people to the version tested so they could check
compatibility.)

But in the short term, before any attempt to add hidden markup or
simply standardize notation, it might seem worthwhile to search code
for particular snippets known to have changed in meaning.  It's hard
in this case: the affected operator is "." , which is presumably
rather common in other uses.

I have recently come across what will be another example.  PARI/GP
just released a new stable version 2.5.0, and along with this
deprecated the operators & and | (which have been shorthand for the &&
and || short-circuit operators).  They continue to work in 2.5 and
2.6, but probably the next version will drop support for them.

Russ/David/Neil, is there a way to search for instances of these so
they can be corrected?  Regular expression like
/(^|\n)\(PARI\).*[^&]&[^&]/s
and
/(^|\n)\(PARI\).*[^|]\|[^|]/s
would give reasonably accurate matches, but I have no way to run those
(short of screen-scraping the entire OEIS!).

Charles Greathouse
Analyst/Programmer
Case Western Reserve University