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include $(GOROOT)/src/Make.$(GOARCH)

TARG=kademlia
GOFILES=\
        nodeid.go\
        routingtable.go\
				contact.go\
				kademlia.go

include $(GOROOT)/src/Make.pkg

zjhmale

Clojure Destructuring Tutorial and Cheat Sheet

(Related blog post)

Simply put, destructuring in Clojure is a way extract values from a datastructure and bind them to symbols, without having to explicitly traverse the datstructure. It allows for elegant and concise Clojure code.

Vectors

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package main

import (
	"fmt"
	"reflect"
)

//function types
type mapf func(interface{}) interface{}

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val a : Option[String] = Some("333")
//a: Option[String] = Some(333)
a.filter(_.length > 1).map(_.length)
//Option[Int] = Some(3)
a.filter(_.length > 6).map(_.length)
//Option[Int] = None
//filter and map function is just for Option type it's just a monad
//def filter(p: A => Boolean): Option[A]
//def map[B](f: A => B): Option[B]

zjhmale

Clojure Destructuring Tutorial and Cheat Sheet

(Related blog post)

Simply put, destructuring in Clojure is a way extract values from a datastructure and bind them to symbols, without having to explicitly traverse the datstructure. It allows for elegant and concise Clojure code.

Vectors

zjhmale

db.tabclicktime.update(
    {tabid: 8},
    {$set: {title: "电视剧"}},
    {multi: true}
);

//-1 -> desc 1 -> asc
db.tabclicktime.find({tabid: 8}).sort({timestamp: -1})

zjhmale

(let [expression (read-string "(+ 1 2 3 4 5)")]
  (cons (read-string "*")
        (rest expression)))
;;=> (* 1 2 3 4 5)

(eval *1)
;;=> 120

(let [expression '(+ 1 2 3 4 5)]
  (cons '* (rest expression)))

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;;
;; NS CHEATSHEET
;;
;; * :require makes functions available with a namespace prefix
;;  and optionally can refer functions to the current ns.
;;
;; * :import refers Java classes to the current namespace.
;;
;; * :refer-clojure affects availability of built-in (clojure.core)
;;   functions.

zjhmale

;;fp语言之所以有抽象能力或者说非fp语言是告诉机器如何一步一步解决问题 而fp语言是向机器描述问题 然后让机器给我们答案其中一个语言原语就是高阶函数 也就是函数可以被当做参数和返回值 还有闭包的存在 函数不再是对象的附属 而是独立的个体 甚至LC中 只有单参函数这一个基本元素却能做到图灵完备 正所谓大道至简

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(defn fizzbuzz [n]
  (let [all-nums (range 0 n)
        folder (fn [fb-str p-num fb-coll]
                 (mapcat (fn [x] (cons fb-str (rest x)))
                         (partition-all p-num fb-coll)))
        fizz (folder "fizz" 3 all-nums)
        buzz (folder "buzz" 5 fizz)
        fizzbuzz (folder "fizzbuzz" 15 buzz)]
    fizzbuzz))