what's the use case for evaling a function object?
On Tue, Aug 27, 2013 at 8:54 PM, Ben Wolfson <wolf...@gmail.com> wrote:
> or, the dreaded "no matching ctor found" exception.
>
> Is there a way to write the function
>
> (defn eval-at-one [f] (eval `(~f 1)))
>
> such that it works when invoked like this:
>
> (eval-at-one (fn [x] x))
> ;; --> 1
>
> and like this
>
> (eval-at-one (with-meta (fn [x] x) {}))
> ;; -> IllegalArgumentException No matching ctor found for class
> clojure.lang.AFunction$1 clojure.lang.Reflector.invokeConstructor
> (Reflector.java:163)
>
> ?
>
> I thought that the object returned by with-meta might be hanging onto the
> original, metadata-less object, which could then be retrieved and used
> without difficulty, but this appears not to be the case.
>
> --
> Ben Wolfson
> "Human kind has used its intelligence to vary the flavour of drinks, which
> may be sweet, aromatic, fermented or spirit-based. ... Family and social
> life also offer numerous other occasions to consume drinks for pleasure."
> [Larousse, "Drink" entry]
>
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