function foo1() {
return {
bar: "hello"
};
}
function foo2() {
return
{
bar: "hello"
};
}
console.log(foo1());
console.log(foo2());
Can I get an explanation why the two functions print out different results even though the code looks the same?
Automatic semicolon insertion
Quoting the specification,
When a
continue,break,return,throw, oryieldtoken is encountered and a LineTerminator is encountered before the next token, a semicolon is automatically inserted after thecontinue,break,return,throw, oryieldtoken.
So the code will become like this
function foo2() {
return; // Note the `;` after `return`
{
bar: "hello"
};
}
The return statement terminates and then there is an object after that, which is basically unreachable code. Since the return statement doesn't return anything explicitly, undefined will be returned.
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