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Function-variables

Notion of function variable.

A function variable is an uninterpreted ACL2 function introduced via defunvar. This macro specifies the arity of the function variable.

A function variable is used in second-order functions and second-order theorems as a placeholder for any function with the same arity.

Naming Conventions

Starting function variable names with ?, as in the examples in the SOFT documentation pages, provides a visual cue for their function variable status. However, SOFT does not enforce this naming convention.

Subtopics

Defunvar
Introduce a function variable.