Data science, ringifying & own blocks II

Hi, again. ( This issue builds up on this one: Data science, ringifying & own blocks )

I managed to achieve this:

But in my opinion, my own "select" block would be nicer this way:
So now, my task is to generate a list of n entries of the type "item 'i' of 'empty list'". This was my first (naive) approach:
Obviously, this won't work. I'm experiencing trouble with "Snap!" trying to read the empty list entry. But this entry has to be empty in order to be useful in the block "map '...' over 'table'".

Any suggestions would be welcome. Feel free to ask for more details. Thanks in advance.

you could try nesting MAP, works for me:

... sorry, hit "enter" too soon. Then your select block definition might look like this:

and you'd use it like this:

Does this make sense to you? Is this what you were looking for?

@jens Thanks. That's it. - As I mentioned in an older posting: "Nice work."

Best wishes for the upcoming SnapCon.

Try using[scratchblocks] (pipe()::control) [/scratchblocks]

Don't teach grandpa how to suck eggs.

(I never thought I'd get to use that line, which is from Robert Heinlein, on the net.)

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Taking that quote out of context makes a silly joke :rofl:.

Apparently it's a real thing, a way to eat soft-boiled eggs. The trick that has to be taught is, of course, that you need two holes in the egg in order to get air pressure working for you.