formatf for positional parameter convenience?

[seancorfield]

If you're using the quoted symbol style queries, it is a nuisance to have to break out of that whenever you want a non-literal value in the query.

It would be nice if there was a quoted symbol style version of something like this:

(sql/format {:select :* :from :users :where [:= :name user-name]})

Proposal:

(sql/formatf '{select * from users where (= name ?1)} user-name) ; was $1 but ? introduces params

It would be purely a convenience wrapper to allow quoted symbol style queries with parameters.

Behind the scenes, it would run (zipmap (map (comp keyword str inc) (range)) args) to create the :params option and then invoke sql/format.

Open question:

• How could options be passed?

[seancorfield]

Since $1 is a valid numbered parameter, I implemented ?1 as a "named" parameter so you get {:params {:1 <value>}}.

[seancorfield]

The "two more possible solutions" use clojure.template and are macros (so no .cljs equivalent right now, since cljs.template does not exist): format& which assumes all local bindings could be variables in a quoted DSL to be substituted and formatv which lets you declare variables to be substituted (which can be local or non-local).

Although the downside is that they are .clj-only, the upside is that they accept all the options, since they are non-variadic wrappers around format, unlike formatf.

[seancorfield]

I'm beginning to settle on formatv as the best option here, even tho' it is .clj-only and a macro. I have removed format& since it duplicates formatv without any of the control. I'll probably remove formatf at this point as well.

I need to add tests and document formatv more extensively.