练习 Clojure LispReader.java

体会lisp的同像性. lisp 从字符串 转为 runtime 的数据结构. 代码是数据 数据是代码

(ns cfenxi.core-test
 (:require [clojure.test :refer :all]
           [cfenxi.core :refer :all]
           [clojure.walk :as w])
 (:import (clojure.lang Compiler$C))
 )
(defn study-read
 "Lisp reader 的时候,会把字符 根据规则解析成 data 具体类型是 java 定义的.
 Symbol PersistentList String MapEntry PersistentArrayMap
 Keyword PersistentList
 "
 [str]
 (let [r (read-string str)]
  (w/prewalk (fn [x] (prn x (type x)) x) r)
  ;(w/prewalk-demo r)
  )
 )

输出

(study-read "(+ 3 2)")
(study-read "(fn [x] (do {:a x}))")

Loading test/cfenxi/core_test.clj... 
(+ 3 2) clojure.lang.PersistentList
+ clojure.lang.Symbol
3 java.lang.Long
2 java.lang.Long
(fn [x] (do {:a x})) clojure.lang.PersistentList
fn clojure.lang.Symbol
[x] clojure.lang.PersistentVector
x clojure.lang.Symbol
(do {:a x}) clojure.lang.PersistentList
do clojure.lang.Symbol
{:a x} clojure.lang.PersistentArrayMap
[:a x] clojure.lang.MapEntry
:a clojure.lang.Keyword
x clojure.lang.Symbol
Loaded