Macros 如何向Clojure中的宏添加第二个参数？

我有以下带有1个参数的Clojure包装宏：

(defmacro with-init-check
"Wraps the given statements with an init check."
[body]
`(if (initialized?)
  ~body
  (throw (IllegalStateException. "GeoIP db not initialized."))))

我想向其中添加

ip版本

，以便检查是否只初始化了

：IPv6

或

：IPv4

。但是，当我尝试此操作时，该参数未被传递：

(defmacro with-init-check
  "Wraps the given statements with an init check."
  [ip-version body]
  `(if (initialized? ip-version)
    ~body
    (throw (IllegalStateException. "GeoIP db not initialized."))))

当我这样使用它时，我在“if let[location…”行中得到“no-this var”：

---

如何将

ip版本

获取到

初始化功能？
用
~
将其解压缩：

(defmacro with-init-check
  "Wraps the given statements with an init check."
  [ip-version body]
  `(if (initialized? ~ip-version) ; unquoted with ~
     ~body
     (throw (IllegalStateException. "GeoIP db not initialized."))))

从docstring推断，您可能还希望允许多个表达式体，并在
do
表达式中取消对它们的拼接：

(defmacro with-init-check
  "Wraps the given statements with an init check."
  [ip-version & body] ; multi-expression bodies with &
  `(if (initialized? ~ip-version)
     (do ~@body) ; unquote-spliced with ~@
     (throw (IllegalStateException. "GeoIP db not initialized."))))

用
~
将其解压缩：

(defmacro with-init-check
  "Wraps the given statements with an init check."
  [ip-version body]
  `(if (initialized? ~ip-version) ; unquoted with ~
     ~body
     (throw (IllegalStateException. "GeoIP db not initialized."))))

从docstring推断，您可能还希望允许多个表达式体，并在
do
表达式中取消对它们的拼接：

(defmacro with-init-check
  "Wraps the given statements with an init check."
  [ip-version & body] ; multi-expression bodies with &
  `(if (initialized? ~ip-version)
     (do ~@body) ; unquote-spliced with ~@
     (throw (IllegalStateException. "GeoIP db not initialized."))))

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