Why a newline between `return` and `(` breaks the code?

Question

Based on the solution of my question: setState fires and render method gets hit, but nothing rerenders

Code works if there is NO newline between return and the (, and fails otherwise.

Example:

this works:

render() 
{
        return (
            <View >
                <ListView dataSource={this.state.beers_ds} renderRow={renderRow.bind(this)} />
            </View>
        ); 
}

But this fails:

render() 
{
        return 
        (
            <View >
                <ListView dataSource={this.state.beers_ds} renderRow={renderRow.bind(this)} />
            </View>
        ); 
}

Why?

Post the code here, in case something changes in the other answer. — Barmar, Sep 19 '17 at 20:48

score 1 · Accepted Answer · answered Sep 19 '17 at 20:50

1

Seems like Automatic Semicolon Insertion might be biting you in the butt. I believe javascript will insert a ; at the end of a return statement automatically.

Why doesn't a Javascript return statement work when the return value is on a new line?

answered Sep 19 '17 at 20:50

Pytth

4,008
24
29

Łukasz Godziejewski · Answer 2 · 2017-09-19T20:56:59.387

1

As answered here: Javascript function fails to return object when there is a line-break between the return statement and the object?

it's just a matter of JS syntax. Semicolons are automatically added and thus the compiler treats

return
  ( sth )

as

return;
  ( sth )

edited Sep 19 '17 at 20:56

answered Sep 19 '17 at 20:51

Łukasz Godziejewski

314
2
6

Why a newline between `return` and `(` breaks the code?

2 Answers2

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