PureBasic Forums - English

blueznl · Post by **blueznl** » Sun Oct 05, 2003 10:37 pm

#true = 1
#false = 0

a.l = true

if a
...
endif

if not a
...
endif

what more can i say?

LCD · Post by **LCD** » Sun Oct 05, 2003 11:11 pm

Good idea, it works fine in Sinclair BASIC, and this was written in 1982. Another good addition from Sinclair Basic would be the string handling
a$="Test"
res$=a$(2 TO 3)
gives "es" in res$.
There is also a bug in Text command. If I try to add a chr()<32 or >127, the added string has a length of 0.

blueznl · Post by **blueznl** » Sun Oct 05, 2003 11:33 pm

a$(2 to 3) might confuse people with string arrays...

and there's mid(), isn't there

GPI · Post by **GPI** » Mon Oct 06, 2003 4:02 pm

LCD wrote:Good idea, it works fine in Sinclair BASIC, and this was written in 1982. Another good addition from Sinclair Basic would be the string handling
a$="Test"
res$=a$(2 TO 3)
gives "es" in res$.

The Basic-Version of the Atari XL/XE do something simulat
Res$=a$(2,3)
This Basic-Variant has also no arrays for strings....

I don't think, that this solution is a good idea. You have mid().

GPI

blueznl · Post by **blueznl** » Mon Oct 06, 2003 4:20 pm

xl... damn, that brings back memories, got 2 400's, one 800, one 600xl with 256kB laying around here somewhere...

LCD · Post by **LCD** » Tue Oct 07, 2003 6:54 pm

blueznl wrote:a$(2 to 3) might confuse people with string arrays...

and there's mid(), isn't there

Sure, there is MID(), but MID uses a length operator for string length, and a$(2 to 3) uses non-relative position pointers, so they can co-exist.
I don't think this will confuse people, as in arrays there is no TO.
I just got now a Atari 800 XL and check this...

blueznl · Post by **blueznl** » Tue Oct 07, 2003 7:29 pm

mmmm true but it wouldn't be a big gain imho, but heh, it's fred's call...

GPI · Post by **GPI** » Tue Oct 07, 2003 7:45 pm

;Sure, there is MID(), but MID uses a length operator for string length, and
;a$(2 to 3) uses non-relative position pointers, so they can co-exist.

I would prefer a new command:
MidPart(a$,start,end)

debug MidPart(a$,2,3)

is better then A$(2 to 3) because there is no confusion with dims. (also i think it is easier to add.)

GPI

blueznl · Post by **blueznl** » Tue Oct 07, 2003 10:39 pm

blueznl · Post by **blueznl** » Wed Oct 08, 2003 10:57 am

i've been thinking about wishes for commands that are easily to emulate in code... there's little need for them, unless they make life a lot easier, but unfortunately it can't be solved all the time

see the following code:

#false = 0
#true = 1

Procedure not(expression)
If expression = false
ProcedureReturn true
Else
ProcedureReturn false
EndIf
EndProcedure

OpenConsole()

a.s="a"
b.s="b"

If not(a.s=b.s)
PrintN("<>")
EndIf

If a.s=b.s
PrintN("=")
EndIf

Repeat
Until Inkey()>""

Post by **Dare2** » Thu Jan 22, 2004 11:50 pm

A NOT operator would be more than nice.

geoff · Post by **geoff** » Sat Jan 31, 2004 12:30 pm

A NOT operator would be more than nice.

I agree.

Kris_a · Post by **Kris_a** » Tue Feb 17, 2004 12:19 am

Can't you just use ~ to get the compliment of the expression? That sounds (and works) just like 'not', AFAIK.

Edit: ah i see

nevermind

Pupil · Post by **Pupil** » Tue Feb 17, 2004 12:27 am

It's not the same, and don't work the same, the only time it works the same is when the expression you use it on is False -then it produces the right result..

Example:

Code: Select all

a = 2 ; This will be interpreted as TRUE in a logical statement
b = ~a ; so this should then be FALSE??

if a
  Debug "a: TRUE"
else
  debug "a: FALSE"
endif

if b
  Debug "b: TRUE"
else
  Debug "b: FALSE"
endif

Post by **Dare2** » Tue Feb 17, 2004 1:05 am

Using ~ and adding 1 seems to be the same as multiplying by -1, that is, it appears to negate a value. Using ~ is like (val * -1) - 1

Whereas my understanding of NOT is that it returns the opposite of true and false:

Code: Select all

If a=0   ;OR a=#false
  a=#true
else
  a=#false
endif

I think Psychophanta created an asm NOT routine for small fast NOTing.