CODEWITHSUNDEEP
clojureclojurescript
Luciano
Luciano

Reputation: 543

IllegalArgumentException: No implementation of method: :as-file of protocol: #'clojure.java.io/Coercions found for class: clojure.lang.Symbol

I'm trying to write a macro for use from ClojureScript to handle file I/O for a Reagent app. I get this error:

IllegalArgumentException: No implementation of method: :as-file of protocol: #'clojure.java.io/Coercions found for class: clojure.lang.Symbol

When I try to do the following:

(def file-string "/Users/luciano/Dropbox/projects/test/resources/blog/test.md")
(get-file file-string)

But I can do this just fine:

(get-file "/Users/luciano/Dropbox/projects/test/resources/blog/test.md")

This is the macro:

(defmacro get-file [fname]
  (slurp (io/file fname)))

What am I doing wrong here?

Upvotes: 1

Views: 322

Answers (2)

Kiran Shila
Kiran Shila

Reputation: 46

What this means is you are trying to call the macro with a symbol that doesn't have a value at runtime.

(def my-file "foo.txt")
(def file-str (get-file my-file))

Will work while

(defn foo [s]
  (get-file s))

(foo "foo.txt")

will not.

Upvotes: 3

Alan Thompson
Alan Thompson

Reputation: 29958

You should not be using a macro for this.

A macro is best viewed as a compiler extension that is embedded in the source code.

All you need is a regular function, like:

(defn get-file 
  [fname]
  (slurp (io/file fname)))

As far as doing I/O from a Reagent app, I'm not sure what you're goal is.

Upvotes: 0

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