Command: roll

Name:
roll - Roll a portion n stack levels k times
Synopsis:
objn ... obj1 n k roll
Description:
roll performs a circular shift of the first n stack levels by k positions. Before this is done, roll removes its arguments from the stack. If k is positive, each shift consists of moving the contents of level 0 to level n-1, thereby moving elements at levels 1 through n-1 up one stack level. If k is negative, each shift consists of moving the contents of level n-1 to level 0, thereby moving elements at levels 1 through n-1 down one stack level.
Examples:
(a) (b) (c) 3 1 roll -> (c) (a) (b) (a) (b) (c) 3 -1 roll -> (b) (c) (a) (a) (b) (c) 3 0 roll -> (a) (b) (c)
Diagnostics:
Raises StackUnderflow error if there are less than n+2 objects on the stack.
SeeAlso: exch rollu rolld rot

Source:
/home/abuild/rpmbuild/BUILD/nest-2.4.1/sli/slistack.cc

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Name:	roll - Roll a portion n stack levels k times
Synopsis:	objn ... obj1 n k roll
Description:	roll performs a circular shift of the first n stack levels by k positions. Before this is done, roll removes its arguments from the stack. If k is positive, each shift consists of moving the contents of level 0 to level n-1, thereby moving elements at levels 1 through n-1 up one stack level. If k is negative, each shift consists of moving the contents of level n-1 to level 0, thereby moving elements at levels 1 through n-1 down one stack level.
Examples:	(a) (b) (c) 3 1 roll -> (c) (a) (b) (a) (b) (c) 3 -1 roll -> (b) (c) (a) (a) (b) (c) 3 0 roll -> (a) (b) (c)
Diagnostics:	Raises StackUnderflow error if there are less than n+2 objects on the stack.
SeeAlso:	`exch` `rollu` `rolld` `rot`
Source:	/home/abuild/rpmbuild/BUILD/nest-2.4.1/sli/slistack.cc