SWI-Prolog -- API-function PL_get

Documentation
- Reference manual
  - Foreign Language Interface
    - The Foreign Include File
      - Exchanging GMP numbers
        
        PL_get_mpz()
        
        PL_get_mpq()
        
        PL_unify_mpz()
        
        PL_unify_mpq()
- Packages

Availability:C-language interface function

int PL_get_mpq(term_t t, mpq_t mpq)

If t is an integer or rational number (term rdiv/2), mpq is filled with the normalised rational number and the function returns TRUE. Otherwise mpq is untouched and the function returns FALSE. Note that mpq must have been initialised before calling this function and must be cleared using mpq_clear() to reclaim any storage associated with it.