Re: Forward declaration of a table and (closure) function

[Steve Litt <slitt@...>]

On Wednesday, July 13, 2011 10:11:02 PM Ross Berteig wrote:
> At 06:54 PM 7/13/2011, Steve Litt wrote:
> >I know the require syntax would definitely work just right if I
> >made
> >the definition of Columns and Columns.new() in a separate
> >module, but I
> >was trying to find a way to have them in the same file but
> >lower down.
> 
> At the time that you attempt to call any function via some
> variable, the function has to be stored in (referenced by,
> actually) that variable.
> 
> You cannot write this:
> 
> local foo
> foo()
> function foo() end
> 
> but the reason why is clearer if the third line were written in
> its equivalent (syntax sugar free) form:
> 
> local foo
> foo()
> foo = function() end
> 
> Now it should be clear that at the time of the attempt to call
> the value in foo, the name is known to be a local variable
> containing nil, but that the assignment of a function to it has
> yet to happen.
> 
> The same situation occurs when you attempt to forward declare
> your Columns object and its methods. You can declare that a
> local variable exists named Columns, but until you've stored
> something in it, you shouldn't be surprised that it holds the
> value nil.

Thanks Ross,

I've already started transferring the code to a module so I can use 
your original syntax. On further reflection, it's really not very 
inconvenient.

Thanks

Steve

Steve Litt
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