I started to use JS Promises in a project recently. I noticed that every time I use .catch my JS linter complains. It does run and does what it should but I looked up the ECMAScript spec and it really looks like it is right: Since catch is a keyword it can not be used as an identifier. As I understand method names are identifiers, so this is invalid:
Promise.reject("Duh").catch(alert);
It should be this instead:
Promise.reject("Duh")['catch'](alert);
What am I missing?
What am I missing?
A property name is not an identifier, it can use any identifier name. From the spec on Property Accessors:
MemberExpression : MemberExpression . IdentifierName
CallExpression : CallExpression . IdentifierName
and identifiers:
Identifier :: IdentifierName but not ReservedWord
You can use any arbitrary identifer name (but not things like integers) in a dot property access, but you can't use those that are [reserved] keywords as identifier, e.g. in a variable or function name.
However, this did change with ES5, back in EcmaScript 3 property names were required to be identiers. That's why you still need to use the bracket notation for keywords if you want to support legacy browsers; and it's the reason why your linter complains about it. Same holds for property names in object literals.
