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1 point by akkartik 4719 days ago | link | parent

What would a table slice even mean?

A sub-table with just the given keys?



1 point by Pauan 4719 days ago | link

Well, sure, but you wouldn't use numeric indices to refer to that. :P It might be something like this:

  (subset x 'foo 'bar 'qux)
As opposed to:

  (x 0 1)
Which would be slice notation, which would work only on ordered sequences, like lists.

Which isn't to say that table subsets would be a bad idea, just that it's a different idea from list slicing, so there shouldn't be any ambiguities with slice notation (which was one of rocketnia's concerns).

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1 point by akkartik 4719 days ago | link

You could implement subsetting at function position, in which case it would be ambiguous. I already use :default in wart, so I don't care too much about that :) But yeah I hadn't thought of how to create ranges of keys. This may not be a good idea. You can't distinguish table lookup from a subset table with just one key/val, for example.

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1 point by Pauan 4719 days ago | link

Well, we could define it so table slicing would only happen with 3 or more arguments:

  (foo 'a 'b 'c)
...but I would consider that to be confusing, and would suggest an explicit function like "slice" or "subset".

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