SWI-Prolog -- current_op/3

Documentation
- Reference manual
  - Built-in Predicates
    - Operators
      - op/3
      - current_op/3
- Packages

Availability:built-in

[ISO]current_op(?Precedence, ?Type, ?:Name)

True if Name is currently defined as an operator of type Type with precedence Precedence. See also op/3.