Re: Re: myWishList

Daniel Bonniot wrote:

>
> Hi Tom,
>
>> I also have a few wish list items for nice.
>> First I think it would be better if multimethods had a more normal 
>> syntax. IE: Outside of a class I could declare:
>>
>> int Object.toInt() throws NumberFormatException
>> {
>>    Integer i = Integer.decode(this.toSting());
>>    return i.intValue;
>> }
>>
>> Then this would add a function to the object class. 
>
>
> Hum, so you're suggesting Object.toInt() instead of toInt(Object 
> this). Why not, but is it really clearer from a Java background? Both 
> are somewhat close to Java, but of course slightly weird at first, as 
> multi-methods are really a concept that does not exist in Java.

I think that it is confusing that it is not declared in a similar syntax 
to how it was called. I would expect that if it was declared
toInt(Object this) { ... }
you would call it like
toInt(something);
Which of course would be confusing because it makes it look like it 
belongs to the current class.

I think a '.' syntax makes it clear that it belongs to the object class. 
Alternatively you could use:
int Object::toInt() { ... }
for a more C++ like syntax.

>> It would be also good if this function would be included in 
>> JavaDocs/NiceDocs. 
>
>
> Yes, isn't it already?

If so great. My concern was that it explicitly be found under the Object 
class's javadoc, despite the fact that it is not generated form that file.

>> The hardest part would be how to handle includes... I guess it would 
>> get imported if you import the class of the name of the file it is 
>> attached to...
>
>
> Nice works at the package level for this. Methods belong to packages, 
> and they are available if the package is imported.
>
>
>> Another thing I would find really useful is to somehow get the 
>> benefits of macro preprocessing. 
>
>
> ...
>
>> In the logger class, I change the debug function to read:
>>
>> //Keyword inlineable means this function will get inlined into it's 
>> caller.
>> inlineable void debug (expression<String> expr) throws Exception
>> { //expr is a valid java expression that will evaluate to a String.
>>    if(shouldlog(Levels.DEBUG)
>>    {
>>        logThis(expr); //Only now is expr evaluated. Because we know 
>> it returns a string, it can't cause problems.
>>        //We have to throw or handle an exception because expr could 
>> throw one.
>>    }
>> }
>>
>> Then the caller would just do:
>> logger.debug(expenciveFunctionCall());
>
>
> You can basically do this already with anonymous functions:
>
> void debug (()->String expr)
> { //expr is a valid java expression that will evaluate to a String.
>   if(shouldlog(Levels.DEBUG)
>      logThis(expr());
> }
>
> Then the caller would just do:
> logger.debug(()=>expensiveFunctionCall());
>
> Of course it could be nice to be able to omit the ()=> at the call 
> site. This would be possible to do it if we added a typing rule T 
> subtype of ()->T (which we could call lazy<T>) and an associated 
> generation of a closure (which is already implemented for ()=> ...).

I saw this in the Docs, but honestly did not understand the explanation. 
What is the ()-> and ()=> supposed to convey? Is this syntax  necessary? 
If anonymous functions are good for situations other that what I 
described, it might be a good idea to get some examples up on the wiki.

>> I don't have a lot of time available, but I do know Java well, and 
>> would be willing to help implement this.
>
>
> Thanks! If there is agreement about this feature, then don't hesitate 
> to contact me, nice-devel or the irc channel for help to get started.
>
> Daniel


Two more random thoughts:
Some of the concepts that Nice has that most other languages don't are 
shared by the D programming language. It might be a good idea if we used 
the same names for them. (And if it fits Nice's style, maybe share a 
similar syntax)
Also is it possible to do compile time unit testing in Nice? If not, I 
could work on it.


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