standard-header

[vemv]

standard-header would be a library similar (yet orthogonal) to how-to-ns.

Probably rewrite-clj is the best tool for the job, since one wants to preserve any metadata, comments, etc

It would ensure that certain clauses are always there, following user configuration.

Examples:

• :refer-clojure :exclude [x y z] is always there
• :require [foo :refer [x y z]] is always there

Use cases

• Replace clojure.core stuff with zero effort
  • e.g. I should not make an active effort to use -> or defn alternatives
  • neither at the IDE level ('keyboard' effort), or at the mental level (I should not have to think 'is this imported?')
• Remove clojure.core stuff deemed dangerous
  • e.g. concat
  • one can still use it, but with clojure.core prefix, which signals "I have thought before doing this"
  • particularly (flatten #{1 2 3}) is tremendously counterintuitive
• Achieve more concise code
  • e.g. it's better to defn than to speced/defn
    • That way, I can always use defn, even if no specing is there, and the day I want to add specing, the effort and diff will be minimal
    • This point is particularly important for users of less-sophisticated IDEs.
• add :require, :as and :refer clauses for extremely used stuff
  • clojure.spec comes to mind
  • coll-of should be refered, it's a unique-enough name which looks ugly with a prefix (unlike spec/def which is perfect)
  • full desired example: [clojure.spec.alpha :as spec :refer [coll-of]]

Considerations

• Formatters that clean unused requires (and :refers) should be able to whitelist standard-header's rules.
  • Maybe not that important if standard-header runs last.