On Thu, Aug 25, 2011 at 5:12 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > While I'm looking at this ... the current implementation has got a > number of very inconsistent behaviors with respect to when it will > expand a variable reference within a psql meta-command argument. > Observe: > > regression=# \set foo 'value of foo' > regression=# \set bar 'value of bar' > regression=# \echo :foo > value of foo > regression=# \echo :foo@bar > value of foo @bar > > (there shouldn't be a space before the @, IMO --- there is because this > gets treated as two separate arguments, which seems bizarre) > > regression=# \echo :foo:bar > value of foo value of bar > > (again, why is this two arguments not one?) > > regression=# \echo :foo@:bar > value of foo @:bar > > (why isn't :bar expanded here, when it is in the previous case?) > > regression=# \echo foo:foo@:bar > foo:foo@:bar > > (and now neither one gets expanded) > > ISTM the general rule ought to be that we attempt to substitute for a > colon-construct regardless of where it appears within an argument, as > long as it's not within quotes. > > Thoughts?
My main thought is that I remember this code being pretty awful - especially with respect to error handling - when I looked at it. A lot of dubious behaviors were more or less compelled by the impossibility of bailing out at an arbitrary point a la ereport(). At least, barring a drastic refactoring of the code, which might not be a bad idea either. No objection if you want to clean some of it up, but you may find it's a larger sinkhole than you anticipate. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
