Re: Representing XML in tables

[Scott Morgan <blumf@...>]

Andy Stark wrote:

> Scott Morgan:-
>
>  
>
> > This seems over kill to my mind as its much simpler to push all the 
> > attribute key/values into their own sub table.
> >    
>
> There are other ways. You can index a table by any value, so we could have
> a convention where the nil value, say, could be used as the index for the
> XML tag:-
>
> xmlRoot = {[nil]= "person"...}
>
>  
Nope, lua dosn't accept nil as an index.

> We would require any XML export module to:-
> - Render string-indexed table elements as attributes;
> - Render integer-indexed table elements as sub-elements;
> - Use the nil-indexed table element as the tag text (or a generic "elem"
> tag if there is no nil index).
>
> This would mean that most Lua tables could be exported to XML reasonably
> even if the author didn't originally design them to be used like this (ie,
> most Lua tables are indexed either by strings or integers or both and
> contain values which are either tables or values which can be converted
> losslessly to strings).
A generic lua table to XML conversion should be trivial. Something like 
the follow jumps to mind:

root = {
 ["something"]="one";
 "two",
 { ["another"]="three" }
}

...becomes...

<table name="root">
 <item name="something">one</item>
 <item name="1">two</item>
 <table name="2">
    <item name="another">three</item>
 </table>
</table>

Could probably make it even simpler, but there is no real problem in the 
direction.

The trick to remember is that a lua table and an XML document are two 
very diffrent structures so we can't expect a simple one to one 
relationship between them.

Scott Morgan