Playing with first class functions

[Mark SiblyKeymaster]

GetValue <T>:T ( key:String,value:T=Null )

I quite like this, but I thought your original point was that GetValue should *fail* if ‘key’ can’t be found? I actually like this idea. Perhaps we could have both, eg:

Monkey

Method GetValue:V( key:K ) Method GetValue:V( key:K,defaultvalue:V )

1 2 3

Method GetValue:V( key:K ) Method GetValue:V( key:K,defaultvalue:V )

In this case, it’d be possible to get exactly current behaviour by using ‘GetValue(key,Null)’ but it’d also pick up existing bugs where you expected something to be in a Map but it wasn’t.

[nerobotParticipant]

Yes, I like what you said in the latest post.

And some changes to docs for these methods where you explain that Null is context specific. Maybe even to create own docs page for Null and place references here from other pages.

What happen if we compare ‘default null’ first class function with keyword Null?

If GetValue ( "test",Null )=Null

Genarally, .Contains () is our big friend.

[nerobotParticipant]

What happen if we compare ‘default null’ first class function with keyword Null?

The answer is – first class function is null until have no assigned values.

Example app:

Monkey

Namespace myapp #Import "<std>" Using std.. Function Main() Local f:Bool() If f=Null Print "#1: func is null" f+=Func If f=Null Print "#2: func is null" f-=Func If f=Null Print "#3: func is null" End Function Func:Bool() Return True End

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

Namespace myapp   #Import "<std>"   Using std..   Function Main()   Local f:Bool() If f=Null Print "#1: func is null" f+=Func If f=Null Print "#2: func is null" f-=Func If f=Null Print "#3: func is null" End   Function Func:Bool() Return True End

Output:

Monkey

#1: func is null #3: func is null

1 2	#1: func is null #3: func is null

Also I found that mx2cc allow us to write weird code:

Monkey

f-=Null ' or +=Null

1	f-=Null ' or +=Null

Is this Null value will generate anonimous new instance or simple will do nothing?

I think the answer is the second case – do nothing. If we have empty / null f and write f+=Null then f still is null.

[Mark SiblyKeymaster]

Also I found that mx2cc allow us to write weird code:

That *is* pretty weird, but it sort of makes sense (to me). I guess it’s a bit like x+=Null where x is an int. I can live with this wrinkle. All other results are what I’d expect (and what I think people would intuitively expect) anyway.

[nerobotParticipant]

I tried it just for testing because we talk about Nulls here.

And I can live with that too.

[Author]

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