(quote x) vs (Value x)

[Timo Mihaljov]

According to the API documentation [1], (quote x) should be equivalent to (Value x), but the the implementations are quite different:

    (defn parse-quote [[_ syn]]
      (cond
        ((some-fn number? keyword? symbol?) syn) {:op :singleton :val syn}
        (vector? syn) (parse-quoted-hvec syn)
        ; quoted map is a partial map with mandatory keys
        (map? syn) (syn-to-hmap syn nil nil false)
        :else (err/int-error (str "Invalid use of quote:" (pr-str syn)))))

    (defn parse-Value [[f & args :as syn]]
      (when-not (#{1} (count args))
        (err/int-error (str "Wrong arguments to Value: " syn)))
      {:op :singleton
       :val (first args)})

This means that e.g. '"Foo" results in an error, whereas (Value "Foo") is accepted.

I'd expect parse-quote to handle vectors and maps specially and handle the :else case exactly like Value. Should I create a ticket for this?

[1] http://clojure.github.io/core.typed/#clojure.core.typed/Val

--
Timo

[Ambrose Bonnaire-Sergeant]

I would accept a patch that enforced

  (def valid-Value? (some-fn symbol? keyword? nil? con/boolean? number? character? string?))

in parse-Value in parse-unparse and parse-ast, and updated the documentation to note exactly what is supported.

It should also say what quote supports (ie. only symbols, keywords and numbers).

Thanks,

Ambrose

[Ambrose Bonnaire-Sergeant]

It's probably also worth adding

true

false

nil

as syntax forms under the quote entry, as they don't exist anywhere else atm.

Thanks

Ambrose

[Timo Mihaljov]

So quote should NOT support characters and strings, even though they are supported by Value? Is there a reason why it can't support everything that passes valid-Value?

--
Timo

[Ambrose Bonnaire-Sergeant]

This is more about being conservative about valuable syntax real estate like quote, and not (yet) being convinced we

need more quote syntaxes.

Thanks,

Ambrose