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• Strin-p

Strin-firstn

Extract the first n characters as a string.

Signature

(strin-firstn n x) → *

Arguments

n — Number of characters to extract.
    Guard (natp n).

x — The input stream.
    Guard (strin-p x).

We just leave this enabled.

Definitions and Theorems

Function: strin-firstn

(defun strin-firstn (n x)
  (declare (xargs :guard (and (natp n) (strin-p x))))
  (declare (xargs :guard (<= n (strin-len x))))
  (let ((__function__ 'strin-firstn))
    (declare (ignorable __function__))
    (coerce (take n (strin-left x))
            'string)))