实例解析js中try、catch、finally的执行规则

try{
 console.log(0);
 }catch (err){
 console.log(1);
 console.log(hello);
 }finally {
 console.log(2);
 }
 //结果分别打印出 0 2
 /
 try{
 a.b.c();
 }catch (e){
 console.log(1);
 console.log(hello);
 }finally {
 console.log(2);
 }
 /
 //结果分别打印出 1 2 报错:hello is not defined
 /
 try{
 a.b.c();
 }catch (e){
 console.log(1);
 try{
  console.log(hello);
 }catch (e){
  console.log(3);
 }
 }finally {
 console.log(2);
 console.log(word);
 } 
 /
 //结果分别打印出 1 3 2 报错:word is not defined
 /
 try{
 a.b.c();
 }catch (e){
 console.log(1);
 console.log(hello);
 }finally {
 console.log(2);
 console.log(word);
 }/
 //结果分别打印出 1 2 报错:word is not defined