1.map一定要初始化，slice可以不用初始化2.pointer一定要初始化varc*Course=>mustinit=>c=&Course{}ornew(Course)3.for-loop的临时变量是一个值会变化的变量varout[]*intfori:=0;i<3;i++{//保存的是i的地址，但是i最后会变成3，slice里全部是3out=appe

importtkinterastkfromtkinterimportttk,messageboximportdb_connectionfromupdateimportUpdatePageimporttime#查询数据库并返回结果deffetch_mistakes(search_text=""):conn1=db_connection.create_connection()cursor=conn1.cursor()

  

     

   

  

      

  

     

    

    

  

   

   

   

    

  funcmain(){messageCh:=make(chanint,10)disconnectCh:=make(chanstruct{},1)fori:=0;i<10;i++{messageCh<-i}gofunc(){for{select{casev:=<-messageCh:

   疑问：前两种情况（1.客户端连接中断2.HTTP请求取消）发生，publish却不expire也不会被cancel，这样会不会有问题？ 

   

      

    WeneedtokeeptwothingsinmindwhileusingthesubstringoperationinGo. First,theintervalprovidedisbasedonthenumberofbytes,notthenumberofrunes. Second,asubstringoperationmayleadtoamemoryleakastheresultings

       

       

    Asaruleofthumb,rememberthatslicingalargesliceorarraycanleadtopotential highmemoryconsumption.Theremainingspacewon’tbereclaimedbytheGC,and wecankeepalargebackingarraydespiteusingonlyafewelements.Using