See `8.11.2.2 Optional Content Membership Dictionaries` -> `VE` entry. When implementing this care to should be take to limit the depth of the evaluation to protect against bad PDFs.
return;
                }
                f (elf.ptn.gnreErrr) {
                  
                  
                  warn(`getTextCntent - gnrng XObject: "${rean}".`);
                  return;
                }
                thrw rean;
              })
            );
            return;
          cae OPS.etGState:
            name = arg[0].name;
            f (name && etyGStateCache.getByName(name)) {
              break;
            }
            next(