Should this work?

[Fred]

We plan to change this in a future version. After some reflexion with Fr34k, we decided to add a compiler directive called Boolean() and accpet such expression only within it. All other use will raise compiler error.

Example:

Code: Select all

Test = Boolean(a = 10 And c = 20) ; Test will contains 0 or 1 depending of the test.
Test = a = 10 And c = 20 ; Test will raise a compiler error.

[Kaeru Gaman]

!WOW!

Boolean Expressions in PureBasic?
Oct.21st now is a Historic Date.

[Demivec]

!WOW!

Boolean Expressions in PureBasic?
Oct.21st now is a Historic Date.

That goes double for me!

[Little John]

Example:

Code: Select all

Test = Boolean(a = 10 And c = 20) ; Test will contains 0 or 1 depending of the test.
Test = a = 10 And c = 20 ; Test will raise a compiler error.

Very cool.
Thanks in advance!

Regards, Little John

[Fred]

Please note the "change in a future version", so don't whine if it doesn't make it for 4.50

[rsts]

. . . so don't whine if it doesn't make it for 4.50

Fred, you give us so much already, we should NEVER whine

cheers

[Little John]

I think we can already now take advantage of a macro for this purpose, which can have the same name.

Code: Select all

Macro boolean (_expression_)
   ((_expression_) Or #False)
EndMacro

;-- Demo
Define a, b, c

a = boolean(Not #False)
Debug a

Debug "--------"

c = 10
a = boolean(b=c)
Debug a
Debug b
Debug c

The macro does no error checking, but it can help us in the following respects:

• Forgotten to enclose 'Not #False' in braces:
  a = Not #False ; doesn't work
  a = boolean(Not #False) ; does work
• The case discussed here:
  a = b = c ; doesn't work as expected
  a = boolean(b=c) ; does work as expected
• From some people's point of view, using this macro might increase readability.
• When the compiler directive Boolean() will be introduced into PureBasic, it is already in our code at the proper place.

Regards, Little John

[Kaeru Gaman]

I just stumbled over this:

We plan to change this in a future version. After some reflexion with Fr34k, we decided to add a compiler directive called Boolean() and accpet such expression only within it. All other use will raise compiler error.

if it will be a compiler directive, does this mean it will be evaluated at compiletime and can only compare constants?

because, Boolean Expressions are really useful to work with variables...

[Mistrel]

That goes double for me!

You could say we're floating on air.

[luis]

if it will be a compiler directive, does this mean it will be evaluated at compiletime and can only compare constants?
because, Boolean Expressions are really useful to work with variables...

Yes, this is unclear to me to. How could be a compiler directive ? To me EnableExplicit is a compiler directive.

BTW: I'm using a BOOL() macro in just the same way in my code

[Fred]

It's a compiler directive which will add the needed ops to returns a boolean values. It will indeed work with any expressions.

[Kaeru Gaman]

ah, wonderful. thank you very much.

[Mistrel]

Is it necessary to have the Boolean keyword? Wouldn't just surrounding an assignment operation be enough to evaluate it as an expression?

[Fred]

May be, but it will be much clearer like that.

[nco2k]

whoa.. thats some good news. thanks!

c ya,
nco2k