My puzzle is the following example:
(defmacro macro1 [x]
(println x))
(defn func1 [x]
(println x))
(defmacro macro2 [x]
`(macro1 ~x)
(func1 x))
(defmacro macro3 [x]
(func1 x)
`(macro1 ~x))
(println "macro2")
(macro2 hello)
(println "macro3")
(macro3 hello)
Surprisingly, the output is:
macro2
hello
macro3
hello
hello
Why the output of macro2 and macro3 are different? In my understanding, all the calling of macro inside macro could be substituted with function (except for the reason of reuse). Anything wrong in my understanding?
Thanks Michael for clarifying. My general question is how to choose between using function or macro inside macro for the purpose of manipulating the s-expression. I wonder whether they can be used exchangeably except that they're evaled at different phases. Another example:
(defn manipulate-func [x]
(list + x 1))
(defmacro manipulate-macro [x]
(list + x 1))
(defmacro macro1 [x y]
[(manipulate-func x) `(manipulate-macro ~y)])
(println (clojure.walk/macroexpand-all '(macro1 (+ 1 2) (+ 3 4))))
;; [(#<core$_PLUS_ clojure.core$_PLUS_@332b9f79> (+ 1 2) 1) (#<core$_PLUS_ clojure.core$_PLUS_@332b9f79> (+ 3 4) 1)]