在C++中，如何从方法返回一个参数，不改变，没有拷贝？//Thisismoreorlessthedesiredsignaturefromthecaller'spointofviewSomeImmutableObjectManipulateIfNecessary(SomeImmutableObjectconst&existingObject){//Dosomework…//...if(manipulationIsNeccessary){//Returnanewobjectwithnewdataetc(preferablywithoutanothercopy)...returnSomeIm