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+---- Thread: for/next/step - did i find a bug? (/showthread.php?tid=396)
for/next/step - did i find a bug? - nitrofurano - 11-03-2011
i don't know if this is a bug, or if i'm defining variable kind wrongly ('j' is not stopping at '0') - thanks in advance!
Code:
border 0:cls
dim i,j as uinteger
for i=0 to 6143 step 3
poke 16384+0+i,128+16+2
poke 16384+1+i,64+8+1
poke 16384+2+i,32+4
next i
lp01:
for j=16384 to 0 step -32
print at 0,0;j;" "
pause 1
for i=0 to 767
poke 16384+6144+i,peek(i+j) band 127
next i
next j
goto lp01Re: for/next/step - did i find a bug? - boriel - 11-03-2011
This has been discussed many times.
You're defining j variable as Uinteger, so a FOR from 16384 DOWNTO 0 will stop when the j variable passes beyond 0, thus negative. This will never happen, because j is always positive (UInteger), so it overflows from 0 to (65535 - 31) and never stops
Re: for/next/step - did i find a bug? - boriel - 11-07-2011
Did you try changing the value type? :roll:
Re: for/next/step - did i find a bug? - nitrofurano - 11-07-2011
boriel Wrote:Did you try changing the value type? :roll:nope, i kept uinteger, because i were only using values from 0 to 65535 - btw, i got that overflow issue you told, and this situation is focusing me on try different aproaches when coding - thanks