encoding names

Hi,
before some time I was discuss with Tatsuo and Thomas about support
for synonyms of encoding names (for example allows to use 
"ISO-8859-1" as the encoding name) and use binary search for searching
in encoding names.  I mean that we can during this change a little clean up encoding 
stuff too. Now PG use for same operations with encoding names different
routines on FE and BE. IMHO it's a little strange. Well, here is a
possible solution:
- use 'enum' instead current #define for encoding identificators  (in pg_wchar.h).- create separate table only with
encodingnames for conversion from  encoding name (char) to encoding numerical identificator,  and searching routines
basedon binary search (from Knut -- see   datetime.c).     All these will *shared* between FE and BE.
 

- For BE create table that handle conversion functions (like current  pg_conv_tbl[]). All items in this table will
availableby access to   array, like 'pg_conv_tbl[ LATIN1 ]', instead current search via for()  cycle.
 
May be also define all tables as 'static' and work with it by some 
routines only. PG has like robust code :-)
Comments, better ideas?
            Karel

-- Karel Zak  <zakkr@zf.jcu.cz>http://home.zf.jcu.cz/~zakkr/C, PostgreSQL, PHP, WWW, http://docs.linux.cz,
http://mape.jcu.cz