multiple assignment

[FlatEarth]

Hi
The requested feature is specified in the codes.

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Define a,b,c = 1,2,3

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Global  a,b,c = 1,2,3

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Protected a,b,c = 1,2,3

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.
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[BarryG]

Why? What's wrong with the following? Your version makes it hard to see which value goes with which variable (especially if you have lots of variables on each line).

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Define a=1,b=2,c=3
Global a=1,b=2,c=3
Protected a=1,b=2,c=3

[FlatEarth]

Not always, but sometimes this syntax is easier. Its existence is harmless and useful. this feature is also available in the lua language.

It may not be very relevant but, the multi-return feature is also useful.

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Procedure MultiRet(a,b,c)
   ProcedureReturn a,b,c
EndProcedure
 
Global a,b,c = MultiRet(10,20,30)

[glennj.0158]

I agree that the construction obfuscates the result. To determine which variable got which value you need to count in. The existing syntax means I just need to find the variable and it's value is immediately apparent.

On the topic of multiple returns, I understand the need to return multiple values. In other languages the CALL command often supports call-by-name in addition to call-by-value.

I have not done it yet but the @ operator purports to get the address of a structure, array, variable or constant. Using that you can pass the address of the variable(s) to be altered in the procedure and "return" as many variables as you want using a clearly defined method.

[skywalk]

Multiple returns are problematic with equations and a procedure in the expression.
y = cos(2*MyMultiReturnFn(x,y,z)) + sin(MyMultiReturnFn(x,y,z)/2)
What is your time saving with this feature?
Remember, you can return a structure or modify the called parameters using @x,@y,@z.

[Mistrel]

You can't return structures as a copy-assignment; only pointers too structures either as a return value or by passing an address as an argument.

[glennj.0158]

Remember, you can return a structure or modify the called parameters using @x,@y,@z.

I tried passing an address as an argument and it didn't work as I expected. I posted the question and the overall answer was that PureBasic does not support indirect reference and you would need to use the Poke(Pointer, ValueToStore) function to actually store information into an external simple variable.

If you have a counter example please share.

Regards
Glenn

[skywalk]

Yes, I read your reply in that topic.
I showed you how to pass ByRef in the Procedure. There are many fine examples in the forum if you search "ByRef".

[Blue]

+1
Excellent suggestion, FlatEarth.
His suggestion does not imply that there's something wrong with the existing coding rules or habits.
It would simply add a quick way of doing the same thing.

[Caronte3D]

+1

[IdeasVacuum]

-1
It's an unnecessary complexity compiler side? Too many unnecessary features and what do you get? Reduced reliability.

[oreopa]

-1. Can't really see a need for this.

To determine which variable got which value you need to count in.

^ This.

[StarBootics]

-1. Can't really see a need for this.

Me too when I have a need for Multiple return I prefer to do something like this :

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Procedure MultipleReturn(a.f, b.f, c.f, *Return00_Float, *Return01_Float)
  
  PokeF(*Return00_Float, ACos(a))
  PokeF(*Return01_Float, ATan2(b, c))  
  
EndProcedure

MultipleReturn(0.25, 0.25, 0.35, @Return00.f, @Return01.f)

Debug Return00
Debug Return01

[mk-soft]

Maybe forgotten, but you do not need PokeF.

You can specify the VarType for ByRef, like a structure.

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Procedure MultipleReturn(a.f, b.f, c.f, *Return00_Float.float, *Return01_Float.float)
  
  *Return00_Float\f = ACos(a)
  *Return01_Float\f = ATan2(b, c)  
  
EndProcedure

MultipleReturn(0.25, 0.25, 0.35, @Return00.f, @Return01.f)

Debug Return00
Debug Return01

[kenmo]

+1 for multiple assignment

1. What's wrong with the existing syntax?
Nothing. It's just objectively longer. The team has added many syntax shorthands over the years.

2. It is too long / hard to read / follow?
It is used all the time in other languages with no problem
especially for pairs or triples, such as

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width, height = 640, 480
x, y, z = 5, 10, 20

If you choose to make your line 10+ definitions and difficult to read, that's your own fault.
You can already do that with colons and putting 10+ commands or data items on one line.

3. It would reduce reliability?
It would have zero change on the compiled executable.
The team has implemented features 100x more complex than this.
I think they can handle parsing this:

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Define.d x, y, z = 0.0, 1.0, 2.0

into this:

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Define.d x = 0.0
Define.d y = 1.0
Define.d z = 2.0

if they choose. It's simpler than macro expansion.



PS. I think we complicated this thread by bringing up multiple returns from procedures.

THAT is a much bigger change, a fundamental change to the language. It would affect the compiler, the syntax, the debugger, and require much more testing.