qrczak@knm.org.pl (Marcin 'Qrczak' Kowalczyk) wrote,
Mon, 8 Jan 2001 17:11:04 +0100 (CET), Marcin 'Qrczak' Kowalczyk <mk167280@zodiac.mimuw.edu.pl> pisze:
A central database can be built around conversions available as values in the program. But it would be a bad idea to take it as the basic identification and require registering to use a conversion.
An important reason is that one can never be sure that a particular encoding has been registered.
I was thinking of having the library itself by default provide a set of standard encodings. Like - as you say later - we usually rely on a set of standard MIME encodings to be available. Given this, most normal users would never have to touch the more complicated Conv type, but just use the string handles to reference these standard encodings. Just like in MIME.
Unless it takes care to import its module ald call the registration function, but in this case he could as well take the conversion itself without the extra indirection.
Not necessarily. Imagine a module StdEncodings, with a function `initStdEncodings'. Then, my program could look like import StdEncodings ... main = do initStdEncondings ... <use encoding "iso-2022-jp"> ... This is simpler than using the fully fledged conversion interface. Moreover, we could require these standard encodings already to be pre-registered. Cheers, Manuel