Is it ok to use count + 1 in ternary operator?

Question

What I want to do is check if there is element in array, if it is, I want to increment counter. Compiler reports error when I do count++ but not when I do count + 1, and it increments correctly. Is it because count++ is operation and not an expression, and count + 1 is expression?

let count = 0;

//not working
count = checkArr(arr) ? count++ : count;

//working
count = checkArr(arr) ? count + 1 : count;

Answer 1

Nothing is forbidden, but some good practice can be adopted.

Mixing up assignation count =, conditioning ?: and post incrementation ++ is a lot inside of a same line.

Always go for the simpliest solution when coding something. In your case :

if (checkArr(arr)) {
  count += 1;
}

is way easier to understand than a ternary which does not seems to be appropriate in that particular context.

---

There are existing tool auditing code quality, as sonarqube, eslint ...

They are always requiring simplicity.

Example about ternary rules :

• https://eslint.org/docs/rules/no-ternary
• https://eslint.org/docs/rules/no-nested-ternary
• https://eslint.org/docs/rules/no-unneeded-ternary

Example about post/pre incrementation :

• https://eslint.org/docs/rules/no-plusplus

They want coder to avoid the use of ++/-- because for some people it can be misleading. A lot of people do not know the difference between ++var and var++ which may led to bugs. Prefer var += 1;.