Re: [Flashforth-devel] For-next and do-loop practise

[om1zz <om...@vo...>]

Mike, thanks! This should definately be put into you FF User Guide!!

?? d) e): K and L are arbitrary values which are added to the loop
counter
?? not sure about the limits (the number of times it runs through
the loop)

a)   B A do ... loop
B A - 1- for ... next

: testa 10 2 - 1- for 0 . next ; ok <#,ram>
testa 0 0 0 0 0 0 0 ok <#,ram>

b)   B A do I ... loop
B A dup !p>r - 1- for @p p+ ... next r>p

: testb 10 2 dup !p>r - 1- for @p . p+ next r>p ; ok <#,ram>
testb 2 3 4 5 6 7 8 ok <#,ram>

c)   D C do
B A do ... I J ... loop
loop

variable j
D C dup !p>r - 1- for
B A dup j ! - 1- for
@p j @ ... p+ 1 j +!
next r>p
next

variable j
: testc
10 2 dup !p>r - 1- for
10 2 dup j ! - 1- for
@p j @ . . p+ 1 j +!
next r>p
next ; ok <#,ram>
testc  2 2 3 3 4 4 5 5 6 6 7 7 8 8 ok <#,ram>

it shall be probably:
------------------------
variable j
: testc
10 2 dup j ! - 1- for
8 3 dup !p>r - 1- for
@p j @ . . p+  
next r>p
1 j +!
next ;

testc 2 3 2 4 2 5 2 6 3 3 3 4 3 5 3 6 4 3 4 4 4 5 4 
6 5 3 5 4 5 5 5 6 6 3 6 4 6 5 6 6 7 3 7 4 7 5 7 6 8 3 
8 4 8 5 8 6 ok <#,ram>


d)   B A do ... K +loop
B A -  K / for ... next

Issue: Here K is usualy a step of any value (not (B-A/K))

e)   D C do
B A do ... I J ... K +loop
L +loop

variable j
D C dup !p>r - K / for
B A dup j ! L / for
@p j @ ... K p++ L j +!
next r>p
next

Issue: Here K and L are usualy steps of any value (not (B-A/K))

f)   B A ?do ... loop
B A - dup if 1- for ... next then

: testf 10 2 - dup if 1- for 0 . next then ; ok <#,ram>
testf 0 0 0 0 0 0 0 ok <#,ram>