Re: need help: some features of Lua don't fit well together

[Konstantin Osipov <kostja@...>]

* Jerome Vuarand <jerome.vuarand@gmail.com> [15/04/14 18:59]:

> Why do you need to distinguish the case when a Lua table is actually
> an array? If you can store an arbitrary map, Lua arrays are just a
> special case of that. In other words:
> 
> function convert_stack_to_set(...)
>     local set = {}
>     local n = 1
>     for each stack value do
>         set[n] = value

No, set elements must be lists, i.e. sequences of fields.
Here we may break this rule if the value is a map or a scalar.

We could convert each stack element to a list with one field, but
then there would be no way to return a list with many fields,
even if the user wanted to do so.

>         n = n + 1
>     end
>     set.n = n -- if you care about trailing nils
>     return set
> end

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