Question

if

true && (function () { console.log('executed'); })()

is ok, then why

true && continue;

or

true && (continue);

doesn’t work, e.g. V8 (Node) throws:

SyntaxError: Unexpected token continue

Answer 1

In JavaScript, there are expressions and statements. Statements can contain expressions, but not the other way round. The statement true && false; is an expression statement.

&& expects two expressions.

Both true and (function() { ... })() are expressions – a boolean expression evaluating to true, and a function expression (wrapped inside parentheses and then called) evaluating to undefined.

continue is a statement, so you cannot use &&. You’ll have to use if because if does accept a statement to be run when the condition is true.

It’s correct behaviour according to the specification and should not be V8-specific.