Date: 19 Apr 1997 00:21:07 -0400
From: Olin Shivers <email@example.com>
- If an item is 'POST, the procedure recurses on the suffix string
(the text from STRING following the match). Including a 'POST in the
list of items is how one gets multiple match/substitution operations.
Upon first reading, this seems completely unmotivated and totally random.
(Or perhaps I simply can't understand the description -- recurses how?)
But perhaps you are emulating some bit of Unix culture here that I'm not
familiar with? I can't figure out why this procedure is called
".../global" either, so perhaps that's another part of the reason why this
seems so utterly random.
In all of your examples the 'POST is the -last- argument pased to
`regexp-substitute/global'. What happens if it occurs somewhere in the
middle? More than once? And in fact, all of your calls to
`regexp-substitute/global', include 'POST as the last argument. Hmm...
I guess the examples make it kind of clear what's going on here. If there
isn't a 'POST anywhere, is `regexp-substitute/global' equivalent to plain
`regexp-substitute'? I think that in the Lisp world we would give a
procedure like this a name like "map-regexp-matches" or something, and
perhaps there might be some lists involved somewhere. This whole
`regexp-substitute/global' thing seems rather compulsively string oriented
-- can't you find some way to use any of the rest of Scheme to make this
Of course I'm the guy who objects to the fact that sub-matches are
identified using numbers, and thus regular expressions have none of the
nice compositional properties that I was taught to appreciate by my
long-time exposure to Scheme. So I can't really be expected to like adding
more procedures that buy ever more deeply into what I see as a flawed
(And I can't seem to interest anybody in addressing that issue either.
Seems like a good thesis topic for a bright undergraduate. Anybody