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• Pad-trim

Trim

Remove whitespace characters from the front and end of a string.

(trim x) removes whitespace characters from the front and end of the string x.

Definitions and Theorems

Function: trim

(defun trim (x)
  (declare (xargs :guard (stringp x)))
  (let* ((bag (list #\Space
                    #\Tab #\Newline #\Page (code-char 13)
                    (code-char 11))))
    (trim-bag x bag)))

Theorem: stringp-of-trim

(defthm stringp-of-trim
  (stringp (trim x))
  :rule-classes :type-prescription)