BUTFIRSTN_CONV
listLib.BUTFIRSTN_CONV : conv
Computes by inference the result of dropping the initial n elements of a list.
For any object language list of the form “[x0;...x(n-k);...;x(n-1)]” ,
the result of evaluating
BUTFIRSTN_CONV “BUTFIRSTN k [x0;...x(n-k);...;x(n-1)]”
is the theorem
|- BUTFIRSTN k [x0;...;x(n-k);...;x(n-1)] = [x(n-k);...;x(n-1)]
Failure
BUTFIRSTN_CONV tm fails if tm is not of the form described above, or
k is greater than the length of the list.