macroexpand-1

macrosince v0.0-3165 clojure.core/macroexpand-1Edit
(macroexpand-1 quoted)

Details:

(only intended as a REPL utility)

If the given quoted form is a macro call, expand it once. NOTE: subforms are not expanded.

See macroexpand if you wish to repeatedly expand a form.

Examples:

See how (-> 2 inc) is progressively expanded:

(macroexpand-1 '(-> 2 inc))
;;=> (inc 2)

(macroexpand-1 '(inc 2))
;;=> (cljs.core/+ 2 1)

(macroexpand-1 '(cljs.core/+ 2 1))
;;=> (js* "(~{} + ~{})" 2 1)

Notice how the nested inc form is not expanded:

(macroexpand-1 '(inc (inc 2)))
;;=> (cljs.core/+ (inc 2) 1)

See Also:

Source docstring:
If form represents a macro form, returns its expansion,
else returns form.
Source code @ clojurescript:src/main/clojure/cljs/core.cljc
(core/defmacro macroexpand-1
  [quoted]
  (core/assert (core/= (core/first quoted) 'quote)
    "Argument to macroexpand-1 must be quoted")
  (core/let [form (second quoted)]
    (if (seq? form)
      `(quote ~(ana/macroexpand-1 &env form))
      form)))