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问题描述

如果我这样做,例如:

 (defmacro qqq []'(toString [this]Qqq)) 
(reify Object(qqq))

reify 看到(qqq)而不是(toString [this]Qqq)



是一个宏,用我自己的东西包装reify调用,但它是更长,更具侵扰性。



如何使我的宏变得更强大,使得通常的宏首先被扩展?



期望类似:

 (defmacro ^ {:priority 100500} qqq []'(toString [this]Qqq))
(reify Object(qqq))

 (defmacro qqq []'(toString [this]Qqq))
(expand-first#{qqq}(reify Object(qqq)))


解决方案

强制给定用户宏首先展开的宏(需要 clojure.walk ):

 (defmacro expand-first [the-set& code 
`(do〜@(prewalk
#(if(and(list?%)(contains?the-set(first%)))
(macroexpand-all%)
%)code)))

谁有想法如何使它更好? >

If I do, for example:

(defmacro qqq [] '(toString [this] "Qqq"))
(reify Object (qqq))

it fails because of reify sees (qqq) instead of (toString [this] "Qqq").

The usual solution is a macro that wraps "reify" call with my own thing, but it is longer and more intrusive.

How to make my macros stronger that usual macros to be expanded first?

Expecting something like:

(defmacro ^{:priority 100500} qqq [] '(toString [this] "Qqq"))
(reify Object (qqq))

or

(defmacro qqq [] '(toString [this] "Qqq"))
(expand-first #{qqq} (reify Object (qqq)))
解决方案

The macro that forces given user macros to expand first (requires clojure.walk):

(defmacro expand-first [the-set & code]
 `(do ~@(prewalk
  #(if (and (list? %) (contains? the-set (first %)))
  (macroexpand-all %)
  %) code)))

Who has ideas how to make it better?

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09-12 11:12