javascript, can this code (nested IF statement) be shorter? - Stack Overflow

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I think below code can be simpleer somehow. Can this code be optimized?

let name = app.short_name;
  if (name === undefined) {
    name = app.name;
    if (name === undefined) {
      name = 'Untitled';
    }
  }

I think below code can be simpleer somehow. Can this code be optimized?

let name = app.short_name;
  if (name === undefined) {
    name = app.name;
    if (name === undefined) {
      name = 'Untitled';
    }
  }

• javascript

Share Improve this question Follow edited Jun 14, 2017 at 7:14 RNA asked Jun 14, 2017 at 6:47 RNARNA 1,09133 gold badges2020 silver badges4343 bronze badges 1

• 5 yes, name could be n :p let name = app.short_name || app.name || 'Untitled'; – Jaromanda X Commented Jun 14, 2017 at 6:48

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3 Answers 3

Sorted by: Reset to default 9

Use Logical OR (||) operator

let name = app.short_name || app.name || 'Untitled';

You could use a default chain with logical OR || in a short-circuit evaluation.

let name = app.short_name || app.name || 'Untitled';

But I suggest to use a variable name different of name, because it is usually a property of window

Javascript will assign what it considers true. If you concat with || (OR) then each value is checked for true until a true value is found and is assigned.

There are a number of values that bee false for example:

• undefined
• 0
• null
• '' (empty String)
• NaN

This is why you could write

let name = app.short_name || app.name || 'Untitled';

because if app.short_name has a value it will be true rather than false and it is assigned. But if it is undefined it will be considered false and app.name will be checked if it is true. If it is undefined it will be again considered false and so finally 'Untitled' is considered and deemed true and assigned to name. Might want to look at this link.

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