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• Natarr

Get-nat

Read the nth element of the natarr array.

In the execution this is an array access, but the logical definition is just a thin wrapper for nth:

Function: nats$ai

(defun nats$ai (stobjs::i natarr$a)
  (declare
       (xargs :guard (and (natarr$ap natarr$a)
                          (integerp stobjs::i)
                          (<= 0 stobjs::i)
                          (< stobjs::i (nats$a-length natarr$a)))))
  (ec-call (nfix (ec-call (nth stobjs::i natarr$a)))))