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Parse-utils

Vl-match-some-token

Compatible with seq. Consume and return a token if it has one of several types. Cause an error if the first token isn't one of the acceptable types.

Signature
(vl-match-some-token types &key (function '__function__) (tokstream 'tokstream)) → (mv errmsg? token new-tokstream)
Arguments: types — Guard (vl-tokentypelist-p types).; function — Guard (symbolp function).
Returns: errmsg? — Type (and (iff errmsg? (not (vl-is-some-token? types))) (iff (vl-warning-p errmsg?) errmsg?)) .; token — Type (vl-token-p token), given (vl-is-some-token? types).

Definitions and Theorems

Function: vl-match-some-token-fn

(defun vl-match-some-token-fn (types function tokstream)
 (declare (xargs :stobjs (tokstream)))
 (declare (xargs :guard (and (vl-tokentypelist-p types)
                             (symbolp function))))
 (let ((__function__ 'vl-match-some-token))
  (declare (ignorable __function__))
  (b*
   ((tokens (vl-tokstream->tokens))
    ((when (atom tokens))
     (vl-parse-error "Unexpected EOF."
                     :function function))
    (token1 (car tokens))
    ((unless (member-eq (vl-token->type token1)
                        types))
     (mv
      (make-vl-warning
           :type :vl-parse-error
           :msg
           "Parse error at ~a0: expected one of ~x1, but found ~s2."
           :args (list (vl-token->loc token1)
                       types (vl-token->type token1))
           :fatalp t
           :fn function)
      nil tokstream))
    (tokstream (vl-tokstream-pop)))
   (mv nil token1 tokstream))))

Theorem: return-type-of-vl-match-some-token.errmsg?

(defthm return-type-of-vl-match-some-token.errmsg?
  (b* (((mv ?errmsg? ?token ?new-tokstream)
        (vl-match-some-token-fn types function tokstream)))
    (and (iff errmsg? (not (vl-is-some-token? types)))
         (iff (vl-warning-p errmsg?) errmsg?)))
  :rule-classes :rewrite)

Theorem: vl-token-p-of-vl-match-some-token.token

(defthm vl-token-p-of-vl-match-some-token.token
  (implies (vl-is-some-token? types)
           (b* (((mv ?errmsg? ?token ?new-tokstream)
                 (vl-match-some-token-fn types function tokstream)))
             (vl-token-p token)))
  :rule-classes :rewrite)

Theorem: vl-match-some-token-fails-gracefully

(defthm vl-match-some-token-fails-gracefully
  (implies (not (vl-is-some-token? types))
           (equal (mv-nth 1 (vl-match-some-token types))
                  nil)))

Theorem: vl-match-some-token-count-strong-on-value

(defthm vl-match-some-token-count-strong-on-value
 (and
     (<= (vl-tokstream-measure
              :tokstream (mv-nth 2 (vl-match-some-token types)))
         (vl-tokstream-measure))
     (implies
          (mv-nth 1 (vl-match-some-token types))
          (< (vl-tokstream-measure
                  :tokstream (mv-nth 2 (vl-match-some-token types)))
             (vl-tokstream-measure))))
 :rule-classes ((:rewrite) (:linear)))

Theorem: equal-of-vl-match-some-token-count

(defthm equal-of-vl-match-some-token-count
 (equal
      (equal (vl-tokstream-measure
                  :tokstream (mv-nth 2 (vl-match-some-token types)))
             (vl-tokstream-measure))
      (if (mv-nth 0 (vl-match-some-token types))
          t
        nil)))