pgsql: Make the to_reg*() functions accept text not cstring.

Make the to_reg*() functions accept text not cstring.

Using cstring as the input type was a poor decision, because that's not
really a full-fledged type. In particular, it lacks implicit coercions
from text or varchar, meaning that usages like to_regproc('foo'||'bar')
wouldn't work; basically the only case that did work without explicit
casting was a simple literal constant argument.

The lack of field complaints about this suggests that hardly anyone
is using these functions, so hopefully fixing it won't cause much of
a compatibility problem. They've only been there since 9.4, anyway.

Petr Korobeinikov

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/ea0d494dae0d3d6fce26bf5d6fbaa07e2ee6c402

Modified Files
--------------
doc/src/sgml/func.sgml | 2 +-
src/backend/utils/adt/regproc.c | 16 ++++++++--------
src/include/catalog/catversion.h | 2 +-
src/include/catalog/pg_proc.h | 16 ++++++++--------
4 files changed, 18 insertions(+), 18 deletions(-)