class:
class MyComponent extends React.Component {
/* Adding state and binding custom methods */
constructor() {
super()
class:
class MyComponent extends React.Component {
/* Adding state and binding custom methods */
constructor() {
super()
变量:名字(identifier) + 值(类型)
基础类型:栈里分配。(栈==函数调用栈)
引用类型:堆里分配。
作业:
1. 闭包与作用域:https://lucifer.ren/fe-interview/#/topics/js/scope&closures
2. 引用和操作符优先级
3. this
/** | |
* RuntimeGlobalsChecker | |
* | |
* You can use this utility to quickly check what variables have been added (or | |
* leaked) to the global window object at runtime (by JavaScript code). | |
* By running this code, the globals checker itself is attached as a singleton | |
* to the window object as "__runtimeGlobalsChecker__". | |
* You can check the runtime globals programmatically at any time by invoking | |
* "window.__runtimeGlobalsChecker__.getRuntimeGlobals()". | |
* |
#!/usr/bin/env bash | |
set -Eeuo pipefail | |
trap cleanup SIGINT SIGTERM ERR EXIT | |
script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &>/dev/null && pwd -P) | |
usage() { | |
cat <<EOF | |
Usage: $(basename "${BASH_SOURCE[0]}") [-h] [-v] [-f] -p param_value arg1 [arg2...] |
class BrowserDetector { | |
constructor() { | |
// 测试条件编译 | |
// IE6~10支持 | |
this.isIE_Gte6Lte10 = /*@cc_on!@*/false; | |
// 测试documentMode | |
// IE7~11支持 | |
this.isIE_Gte7Lte11 = !!document.documentMode; |
// multi-part | |
// client.mjs | |
import fs from "fs"; | |
import path, { dirname } from "path"; | |
import request from "request"; | |
import { fileURLToPath } from "url"; | |
var r = request.post("http://localhost:7001/low-code/api/v1/magic", function( | |
err, |
// 根据 traceId 可以找出一个链路的所有请求 | |
// 根据 spanId 可以就上面找到的所有请求画出调用树🌲 | |
function a({ traceId, spanId, random }) { | |
if (random > 0.5) { | |
b({ traceId, spanId: spanId + "." + 1, random: Math.random() }); | |
} else { | |
c({ traceId, spanId: spanId + "." + 1, random: Math.random() }); |