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Reverse, Reversed

Syntax

Reverse(V:LIST):NULL
Reversed(L:LIST):NULL

where V is a variable containing a list in the first case.
    

Summary

reverse a list

Description

The the function Reverse reverses the order of the elements of the list in V, returning Null. It does *not* return the reversed list, but instead changes L itself. The function Reversed returns the reversed list without changing L.

example

    
L := [1,2,3,4];
Reverse(L);
L;  -- L has been modified
[4, 3, 2, 1]
-------------------------------
M := [1,2,3,4];
Reversed(M);  -- the reversed list is returned
[4, 3, 2, 1]
-------------------------------
M;  -- M has not been modified
[1, 2, 3, 4]
-------------------------------
        
    

See Also