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2 points by kinnard 2131 days ago | link | parent

Does the necessity of quasiquote + unquote feel natural?

  (= tpipe {todo 
              '({id 1 cont "get eggs" done '(nil)}
                {id 23 cont "fix toilet" done '(nil)})
            week '(nil)
            today '({id 83 cont "Build something that works in arc" done '(nil)})
This won't work:

  arc> tpipe!todo.1!id
One must employ (list) or quasiquotation

    (= npipe {todo 
                (list {id 1 cont "get eggs" done '(nil)}
                      {id 23 cont "fix toilet" done '(nil)})
              week '(nil)
              today (list {id 83 cont "Build something that works in arc" done '(nil)})
              done (list {id 44 cont "Research Ordered Associative Arrays" done '(2019 1 21)})})

    (= unqpipe {todo 
                `(,{id 1 cont "get eggs" done '(nil)}
                  ,{id 23 cont "fix toilet" done '(nil)})
                week '(nil)
                today `(,{id 83 cont "Build something that works in arc" done '(nil)})
                done `(,{id 44 cont "Research Ordered Associative Arrays" done '(2019 1 21)})})


3 points by rain1 2122 days ago | link

I think you should have to quote them. Like how you have to quote lists:

    '(foo bar)
is just a list, but

    (foo bar)
will either call the function foo or error if it doesn't exist.

So in a similar way

    {foo "bar"}
should give a syntax error, but maybe it can have some kind of semantic meaning later. I've been considering that square brackets could be used for assignment/local binding, to cut down on the need for LET (not necessarily in arc just in lisp in general).

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2 points by i4cu 2122 days ago | link

> should give a syntax error...

I don't agree. quoting a list is a way to protect the expression from evaluation, in this case because round brackets normally indicate an expression that needs to be called. A table literal {...} doesn't need protection from evaluation as a callable expression as it's just data and like any other data it should evaluate to itself. And, frankly, it would really suck having to protect that data everywhere in my code because someone wants a really nuanced use case to work.

Really what should happen is that [] should be implemented such that we don't need to protect lists of data.

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2 points by i4cu 2122 days ago | link

> Really what should happen is that [] should be implemented such that we don't need to protect lists of data.

I should point out that I don't think this can happen since square brackets are reserved for other uses in Arc.

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2 points by rain1 2122 days ago | link

I see what you mean, making it self evaluate seems like the best option.

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