• Top
    • Documentation
    • Books
    • Boolean-reasoning
    • Projects
    • Debugging
    • Std
    • Proof-automation
    • Macro-libraries
    • ACL2
      • Theories
      • Rule-classes
      • Proof-builder
      • Recursion-and-induction
      • Hons-and-memoization
      • Events
      • Parallelism
      • History
      • Programming
        • Defun
        • Declare
        • System-utilities
        • Stobj
        • State
        • Mutual-recursion
        • Memoize
        • Mbe
        • Io
        • Defpkg
        • Apply$
        • Loop$
        • Programming-with-state
          • Error-triple
          • Cbd
          • State-global-let*
          • Last-prover-steps
          • @
          • Assign
          • Read-run-time
          • Canonical-pathname
          • F-put-global
          • Unsound-eval
          • Setenv$
          • Er-progn
          • Read-ACL2-oracle
            • With-live-state
            • F-get-global
            • Getenv$
            • Pprogn
            • Get-real-time
            • Makunbound-global
            • Get-cpu-time
            • F-boundp-global
            • Probe-file
          • Arrays
          • Characters
          • Time$
          • Defmacro
          • Loop$-primer
          • Fast-alists
          • Defconst
          • Evaluation
          • Guard
          • Equality-variants
          • Compilation
          • Hons
          • ACL2-built-ins
          • Developers-guide
          • System-attachments
          • Advanced-features
          • Set-check-invariant-risk
          • Numbers
          • Efficiency
          • Irrelevant-formals
          • Introduction-to-programming-in-ACL2-for-those-who-know-lisp
          • Redefining-programs
          • Lists
          • Invariant-risk
          • Errors
          • Defabbrev
          • Conses
          • Alists
          • Set-register-invariant-risk
          • Strings
          • Program-wrapper
          • Get-internal-time
          • Basics
          • Packages
          • Oracle-eval
          • Defmacro-untouchable
          • <<
          • Primitive
          • Revert-world
          • Unmemoize
          • Set-duplicate-keys-action
          • Symbols
          • Def-list-constructor
          • Easy-simplify-term
          • Defiteration
          • Fake-oracle-eval
          • Defopen
          • Sleep
        • Operational-semantics
        • Real
        • Start-here
        • Debugging
        • Miscellaneous
        • Output-controls
        • Macros
        • Interfacing-tools
      • Interfacing-tools
      • Hardware-verification
      • Software-verification
      • Math
      • Testing-utilities
    • Programming-with-state
    • ACL2-built-ins

    Read-ACL2-oracle

    Pop the oracle field of the state

    ACL2 has a mutable `state' that contains a number of fields; see state. One of these fields is a list, called the acl2-oracle field. There are no constraints on the elements of this list; thus, you will not be able to prove anything about those elements. However, as a convenience, ACL2 permits you to evaluate the form (read-acl2-oracle state), which returns the multiple value (mv nil nil state).

    The ACL2 implementation uses read-acl2-oracle, but you will likely find this function to be useless unless you do advanced, scurrilous things using trust tags (see defttag).

    The following definition is the logical definition of read-acl2-oracle, but as explained above does not really characterize its behavior under the hood.

    Function: read-acl2-oracle

    (defun read-acl2-oracle (state-state)
      (declare (xargs :guard (state-p1 state-state)))
      (mv (null (acl2-oracle state-state))
          (car (acl2-oracle state-state))
          (update-acl2-oracle (cdr (acl2-oracle state-state))
                              state-state)))