Motivated by Bug 19409 [1] I decided to do something about a wart that
has bugged me for a while, namely the requirement to write stuff in
system_views.sql if you need to specify default values for function
arguments. Here's my attempt. The first patch here sets up the required
infrastructure. genbki.pl creates a file called function_defaults.sql
which is run by initdb at the appropriate time. There are two new fields
in pg_proc.dat entries: proargdflts,and provariadicdflt. These are
parsed and the appropriate CREATE OR REPLACE statement is generated and
placed in function_defaults.sql. The second patch applies this treatment
to 37 function definitions and removes the corresponding statements from
system_views.sql. This gets us closer to having pg_proc.dat as a single
source of truth.
+1 for the attempt. My preference would be for allowing CREATE OR REPLACE to specify an oid, but that's a non-starter for bootstrapping purposes, so this is the next best option.
The defaults read a little funny in that a human reader must line up the defaults right-to-left to then determine a given parameter's default, if any. For example:
proname => 'json_strip_nulls', prorettype => 'json',
- proargtypes => 'json bool', prosrc => 'json_strip_nulls' },
+ proargtypes => 'json bool',
+ proargnames => '{target,strip_in_arrays}', proargdflts => '{false}',
+ prosrc => 'json_strip_nulls' },
Perhaps we could require proargdflts to pre-pad with empty values
proargdflts => '{,false}'
or even be a hash
proargdflts => { strip_in_arrays => 'false' }
which I will grant you is wordy, but its definitely clearer.
