todo app remaining tasks reducer func fixed and clarified

[sulmanen]

Reduce func in get remaining() looked funny in the example. Maybe this is clearer.

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[sulmanen]

I signed it!

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[gkalpak]

Indeed count + +!todo.done was a little too much :)
Even simpler would be:

this.todos.filter((todo: Todo) => !todo.done).length

[sulmanen]

why yes, much better.

[wardbell]

I agree that it reads better. The reduce would be more efficient if we had a gazillion todos ... an absurdity in itself. Accepting ... after taking it the last step (because of type inference):

return this.todos.filter(todo => !todo.done).length;

Snuck in a few similar cleanups and spacing for readability.

Thanks.