JavaScript
JavaScript mixed ?? with || or && without parentheses
SyntaxError: cannot use ?? unparenthesized within || and && expressions
JavaScript does not allow nullish coalescing to be combined directly with logical OR or AND without explicit grouping.
Observed message
SyntaxError: cannot use ?? unparenthesized within || and && expressions
Why it happens
- Code combines ?? with || or && in one expression without grouping.
- A refactor replaced || with ?? but left mixed logical operators unparenthesized.
- Expression precedence assumptions do not match JavaScript grammar rules.
How to fix it
- Wrap the intended part of the expression in parentheses.
- Split the expression into smaller steps if the logic is unclear.
- Choose one operator pattern deliberately instead of mixing them implicitly.
