@typenumber_with_remark::{number,String.t}@specadd(number,number)::number_with_remarkdefadd(x,y),do:{
键-字符串:键(例如“a”)或键符号(例如“空格”) Bind_fun_tokey-releaseeventofkey.If_fun_is`None`,eventbindingsareremoved.Remark