Function pointers should auto-cast to Bool

[sicilicaParticipant]

This is a pretty simple thing, and I’m sure someone will disagree with me, but it would be a really nice quality of life improvement if Function types implicitly cast to Bools.

This works with objects, of course. Compare this:
<pre class=”lang:monkey decode:true “>Class FooBar

Field entity:Entity

Method Update()
If entity
entity.Update()
Endif
End

End

And this:
<pre class=”lang:monkey decode:true”>Class FooBar

Field updateCallback:Void()

Method Update()
If updateCallback <> Null ‘ doesn’t work without “<> Null”
updateCallback()
Endif
End

End

It seems silly that I have to explicitly tell the compiler what I mean, since what it means for a function pointer to be “truthy” is pretty well understood.

[Matthew SmithParticipant]

I believe the ? operator will be added soon which will verify if an object is null before using it:
http://monkey2.monkey-x.com/monkey2-roadmap/

so you could do entity?.Update() in you example.

[Mark SiblyKeymaster]

He’s talking about something different here, ie: whether a function pointer is null or not, not an object.

I have no general problem with this change – I think it was disabled because it confused the c++ compiler but it should be easy enough to fix.

 

Another thing to note is that you can actually call a ‘null’ function pointer – it will perform a ‘NOP’ and return a Null value of the return type.

[sicilicaParticipant]

You can call null functions? That’s – interesting. I can’t think of a lot of reasons that’d be useful, but it’s good to know.

The object ?. operator would be a lot like Option objects in languages like Scala, it sounds like. I guess having both that and a default behavior for null function calls could clean up a lot of boilerplate safety checks. Sweet.

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