Re: [Qexo-general] Globals

[Per Bothner]

Seshukumar Venkata Adiraju wrote:
> Can define be used to change a value of a binding after it is defined
> once.
>
> Can I do something like,
>
> xq.define("var1", "value1");
>
> And then later 
>
> xq.define("var1", "value2");

It should work, but I'd recommend against it.  Since XQuery is
a side-effect-free language, the implementation is free to treat
a variable as constant - depending of course on how it is called.
(It's probably ok but inefficient if you re-parse the query.)

> In my application I'm presenting the user a list of values from which he
> selects.
> The user might come back to this and change his selection and execute
> xquery again.

In that case, I think it would be better to compile a function (as
I showed in previous email), and call it with different parameters.

A stable, documented, and efficient ABI (i.e. the Java-equivalent
result of compiling XQuery) is not really a feature of Qexo yet,
but it will be one of the main goals fo the 1.8 version.


--
        --Per Bothner
address@hidden   http://per.bothner.com/