How to display placeholders in AngularJS for undefined expression values?

Question

If I have an expression {{ x }} and x is undefined or null, then how can I display a placeholder for it?

I provided one solution

Answer 1

Implementing default-ish filters works, but if you're using only numbers you can use angular's own number filter

If the input is null or undefined, it will just be returned. If the input is infinite (Infinity or -Infinity), the Infinity symbol '∞' or '-∞' is returned, respectively. If the input is not a number an empty string is returned.

{{ (val | number ) || "Number not provided"}}