#comma operator

Is the comma operator in C++ a hidden gem or a lurking danger? In 'It's just ',' - The Comma Operator,' I explore its surprising dangers. Could using it lead to subtle, unnoticed errors? Let’s uncover the truth together! #cpp #cppsenioreas #cpp17 #cpp23

We all know that every ‘,’ matters in this language, so I decided to talk directly about that letter today. So, how much impact can be for such a small little character? The Comma Operator This operator comes from C, where it tells the compiler to evaluate all the expressions (left to right) and to return the result of the latest evaluated expression. For example: int a, b; a = 5, b = 4, b +=…

The limitations of the comma operator

I have read this question and I want to add to it that what are the things that can not be done using the comma operator.This has confused me a lot.As I can do :

int arr[3]; arr[0]=1,arr[1]=2,arr[2]=3;

But when I do :

int arr[3],arr[0]=1,arr[1]=2,arr[2]=3;

It gives me a compiler error.

I want to ask that what are the limitations of the comma operator in real practice?

Best Answer

One thing…

comma 연산자는 원래 한 표현식(expression)이 있어야하는 곳에서 2개 이상 표현식을 쓰려고 할때 사용합니다. comma 연산자로 묶인 표현식들은 좌측 표현식부터 차례로 평가(evaluation) 후 마지막 가장 우측 표현식의 결과값이 return 됩니다.전체 표현식의 결과값이 됩니다.( 전웅님 충고 감사합니다.)

연산자 우선 순위에 따라 결과 값이 달라지므로 주의깊게 사용해야 합니다.