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Std/system/event-name-queries

Constant-symbolp

Check if a symbol names a constant, i.e. it has a const property.

Signature
(constant-symbolp sym wrld) → yes/no
Arguments: sym — Guard (symbolp sym).; wrld — Guard (plist-worldp wrld).
Returns: yes/no — Type (booleanp yes/no).

This function is named in analogy to the function-symbolp built-in system utility.

Definitions and Theorems

Function: constant-symbolp

(defun constant-symbolp (sym wrld)
  (declare (xargs :guard (and (symbolp sym)
                              (plist-worldp wrld))))
  (let ((__function__ 'constant-symbolp))
    (declare (ignorable __function__))
    (not (eq (getpropc sym 'const t wrld) t))))

Theorem: booleanp-of-constant-symbolp

(defthm booleanp-of-constant-symbolp
  (b* ((yes/no (constant-symbolp sym wrld)))
    (booleanp yes/no))
  :rule-classes :rewrite)

Theorem: constant-symbolp-forward-to-symbolp

(defthm constant-symbolp-forward-to-symbolp
  (implies (and (constant-symbolp fn wrld)
                (plist-worldp wrld))
           (symbolp fn))
  :rule-classes :forward-chaining)