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Error-checking

Ensure-function/lambda-closed

Cause an error if a function or lambda expression is a non-closed lambda expression.

Signature
(ensure-function/lambda-closed fn/lambda description error-erp error-val ctx state) → (mv erp val state)
Arguments: fn/lambda — Function or lambda expression to check.
Guard (pseudo-termfnp fn/lambda).; description — Guard (msgp description).; error-erp — Flag to return in case of error.; error-val — Value to return in case of error.; ctx — Context for errors.
Returns: erp — Type (implies erp (equal erp error-erp)).; val — Type (and (implies erp (equal val error-val)) (implies (and (not erp) error-erp) (not val))) .

This error-checking function is useful after calling ensure-function/macro/lambda (which returns the pseudo-termfnp) to handle functions and lambda expressions uniformly. The description parameter should describe the function or lambda expression.

Definitions and Theorems

Function: ensure-function/lambda-closed

(defun ensure-function/lambda-closed
       (fn/lambda description
                  error-erp error-val ctx state)
  (declare (xargs :stobjs (state)))
  (declare (xargs :guard (and (pseudo-termfnp fn/lambda)
                              (msgp description))))
  (b* (((unless (or (symbolp fn/lambda)
                    (lambda-closedp fn/lambda)))
        (er-soft+ ctx error-erp error-val
                  "~@0 must be closed." description)))
    (value nil)))

Theorem: return-type-of-ensure-function/lambda-closed.erp

(defthm return-type-of-ensure-function/lambda-closed.erp
  (b*
   (((mv ?erp ?val ?state)
     (ensure-function/lambda-closed fn/lambda description
                                    error-erp error-val ctx state)))
   (implies erp (equal erp error-erp)))
  :rule-classes :rewrite)

Theorem: return-type-of-ensure-function/lambda-closed.val

(defthm return-type-of-ensure-function/lambda-closed.val
  (b*
   (((mv ?erp ?val ?state)
     (ensure-function/lambda-closed fn/lambda description
                                    error-erp error-val ctx state)))
   (and (implies erp (equal val error-val))
        (implies (and (not erp) error-erp)
                 (not val))))
  :rule-classes :rewrite)

Subtopics

Ensure-function/lambda-closed$: Calls ensure-function/lambda-closed with ctx and state as the last two arguments.