the to_char() source code is large, here are regression tests for
numeric/timestamp/int8 part. It is probably enough test for formatting
code in the formatting.c module. The others (float4/float8/int4) types
share this formatting code and eventual bugs for these types aren't
few probable.
Patch fix timestamp_to_char() for infinity/invalid timestamp too.
Karel
Implement "date/time grand unification".
Transform datetime and timespan into timestamp and interval.
Deprecate datetime and timespan, though translate to new types in gram.y.
Transform all datetime and timespan catalog entries into new types.
Make "INTERVAL" reserved word allowed as a column identifier in gram.y.
Remove dt.h, dt.c files, and retarget datetime.h, datetime.c as utility
routines for all date/time types.
date.{h,c} now deals with date, time types.
timestamp.{h,c} now deals with timestamp, interval types.
nabstime.{h,c} now deals with abstime, reltime, tinterval types.
Make NUMERIC a known native type for purposes of type coersion. Not tested.