true and false for bool

[kryton9]

We have the bool type in oxygen, but no corresponding true or false to go with it. Would be a nice addition.

This gives errors:

Code: OxygenBasic

1. bool f = false
2. bool t = true
3.  
4. print "should be false " f
5. print "should be true " t

[kryton9]

Also found these sort of oddities as noted in the code.

Code: OxygenBasic

1. int false = -2
2. int true = 1
3.  
4. bool f = false
5. bool t = true
6.  
7. 'this works
8. print "should be false " str( not( t ) )
9. print "should be true "  str( not( f ) )
10.  
11. 'this works
12. print "should be false " str not(t)
13. print "should be true "  str not(f)
14.  
15. 'this doesn't give correct answer
16. print "should be false " str( not t )
17. print "should be true "  str( not f )
18.  
19. 'this gives errors
20. 'print "should be false "  not t
21. 'print "should be true "   not f
22.  
23. 'this gives errors also
24. 'print "should be false "  not( t )
25. 'print "should be true "  not( f )

[Charles Pegge]

I'll take a closer look at this, Kent.

Currently We do not have a true single bit Boolean or a built-in true/false equates.

Boolean will translate to sys and the true condition usually returns -1 and false is always zero.

Any zero value number, including floats is logically evaluated as false, otherwise it is true.

Oxygen will also evaluate empty strings and null strings to false (0) and all other strings to true. (-1)

Charles

[kryton9]

I think there was a typo in your reply Charles, true -1...
anyways here is c++ output for bool   true 1     false 0

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[Charles Pegge]

A True sets all the bits in the eax register to 1 including bit 31, the sign bit: hence -1.

Charles

[efgee]

You both are correct:

basic true is -1
c/c++ true is 1

Only hope that if the oxygen compiler sees C code it treats true in c mode not basic.

Personally I prefer:
true 1
false 0
error -1
but nobody would care anyhow... 

[Charles Pegge]

I could mask off all the other bits when returning or assigning bool.

Charles

[kryton9]

I have no idea what that means Charles, but I think matching c++ way will be easier. I will do not on that test case to see what c++ gives.
I saw -2 somewhere in my tests... could have been in oxygen or c++... will post screenshot here.

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