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Start your free trialJames Estrada
Full Stack JavaScript Techdegree Student 25,866 PointsQuestion about arrow functions as values in object literal
As I understand, an arrow function is a function expression, therefore a semicolon is more technically correct to have at the end. This has been the standard practice as a standalone arrow function, but when it's inside an object literal as a value, the console gives me a syntax error when I add the semicolon.
const nameActions = {
remove: () => {
ul.removeChild(li);
};, // why applying standard practice throws an error?
...
...
};
The above code throws an Uncaught SyntaxError: Unexpected token ';' Why?
1 Answer
Steven Parker
231,236 PointsSemicolons do not go at the end of expressions, they go at the end of statements.
When you create "a standalone arrow function", the arrow function expression would be the last thing in an assignment statement. In that situation, a semicolon would be appropriate (and a "best practice").
In the object literal, the expression is not part of a statement, so a semicolon is incorrect syntax.
Giles Lewey
Full Stack JavaScript Techdegree Student 11,349 PointsGiles Lewey
Full Stack JavaScript Techdegree Student 11,349 PointsIsn't
Const a = 2; an expression?
Steven Parker
231,236 PointsSteven Parker
231,236 PointsEssentially, expressions are evaluated to produce a value, and statements are executed to make something happen.
This is a statement that declares the variable "a" and gives it a value. It's making something happen.
On the other hand, the right side of an assignment (in this case, just "2") would be an expression. It produces a value.