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let a,b=1;
// 注释
var obj = {
    "name":1+3*2,
      "func":function add(a,b){
      let a1=3;
      return a+b
    }
}
function add(a,v){
    return a+v;
}
let xx;
xx = 12;

let fs = require("fs");//读取文件
let parser = require("@babel/parser");//解析语法树
let types = require("@babel/types");//获取类型
let generator = require("@babel/generator").default;//语法树转换成代码
let traverse = require("@babel/traverse").default;//遍历语法树

let jscode = fs.readFileSync("./input.js", { encoding: "utf-8" });
let ast = parser.parse(jscode, { sourceType: "module" });

let one = types.variableDeclaration("let",[
    types.variableDeclarator(types.identifier("a"),null),
    types.variableDeclarator(types.identifier("b"),types.numericLiteral(120))
]);
console.log(generator(one).code);

let two = types.variableDeclaration("var",[
    types.variableDeclarator(types.identifier("obj"),types.objectExpression([
        types.objectProperty(types.stringLiteral("name"),types.binaryExpression("+",types.numericLiteral(1),types.binaryExpression("*",types.numericLiteral(3),types.numericLiteral(2)))),
        types.objectProperty(types.stringLiteral("func"),types.functionExpression(null,[types.identifier("a"),types.identifier("b")],types.blockStatement([
            types.variableDeclaration("let",[types.variableDeclarator(types.identifier("a1"),types.numericLiteral(3))]),
            types.returnStatement(types.binaryExpression("+",types.identifier("a"),types.identifier("b")))
        ])))
    ]))
]);
console.log(generator(two).code);


let three = types.functionDeclaration(types.identifier("add"),[types.identifier("a"),types.identifier("v")],types.blockStatement([types.returnStatement(types.binaryExpression("+",types.identifier("a"),types.identifier("v")))]));
console.log(generator(three).code);
let four = types.variableDeclaration("let",[types.variableDeclarator(types.identifier("xx"),null)]);
console.log(generator(four).code);
let five = types.expressionStatement(types.assignmentExpression("=",types.identifier("xx"),types.numericLiteral(12)));
console.log(generator(five).code);