SRFI 130 and SRFI 115 interaction
John Cowan 28 Apr 2016 00:31 UTC
I'm planning to add a new paragraph to SRFI 130 explaining how it should
interoperate with SRFI 115 if both are present in the same implementation.
I think the first sentence should be uncontroversial, but the second
sentence may require some discussion.
In a Scheme implementation that provides both this SRFI and
SRFI 115 : Scheme Regular Expressions, the procedures of SRFI
115 that accept start and end index arguments must be modified
to also accept start and end cursor arguments. Furthermore, the
procedures regex-match-submatch-start and regex-match-submatch-end
must return cursors rather than indexes.
Alternatively, the "must" in the second sentence could be replaced by
"should" or even "may", since it is possible to do conversions with
string-cursor->index and string-index->cursor, which are identity
functions if their arguments are an index or cursor respectively.
As yet another possibility, two new interfaces could be provided,
regex-match-submatch-start-cursor and regex-match-submatch-end-cursor.
If there are comments or objections, please raise them now.
--
John Cowan http://www.ccil.org/~cowan xxxxxx@ccil.org
At the end of the Metatarsal Age, the dinosaurs abruptly vanished.
The theory that a single catastrophic event may have been responsible
has been strengthened by the recent discovery of a worldwide layer of
whipped cream marking the Creosote-Tutelary boundary. --Science Made Stupid