Use destructuring more and minor tweaks

[XhmikosR]

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[XhmikosR]

@bezoerb if you could also add a test so that we cover the undefined case that would be perfect :)

[bezoerb]

@XhmikosR: just took a closer look and i think we don't need the || {} because as of my understanding it can't return undefined as we're only looping over the elements which have been previously selected.

I thought one might just pass an invalid type to the function but this is also already handled.

[XhmikosR]

I just reverted the fallback addition, can you confirm all is good?