> Eg Behead has a dyadic form
> Drop }. but Curtail does not ... are there
> some better (future) plans
> for a dyadic curtail
Dyadic }. can be used to curtail multiple items. Use a negative LHA. For
example:
_3 }. 1 2 3 4 5
1 2
> back=: back, {: stack
> stack=: }: stack
You can split a list of items into two variables in a single operation like
this:
stack =. 1 2 3 4 5
'stack back' =. _2 (}. ; {.) stack
stack
1 2 3
back
4 5
I don't know what swap does in Forth, but is this what you're looking for?
swap =. ,~
1 swap 2
2 1
Or are you trying to reorder your stack?
swap =: (<_2 _1)&C.
swap ;: 'bottom middle top'
+------+---+------+
|bottom|top|middle|
+------+---+------+
Or maybe you like the old fashioned way:
swap =. 4 : 'x ,: y =. y 22 b. x =. x 22 b. y =. y 22 b. x'&.(a. i.
3!:1"1)
1 swap 2
2 1
:)
-Dan
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