CompletionAction complete(StringRef Buffer, size_t Pos) const override;
static std::string getCommonPrefix(const std::vector<Completion> &Comps);
virtual std::vector<Completion> getCompletions(StringRef Buffer,
CompletionAction complete(StringRef Buffer, size_t Pos) const override;
static std::string getCommonPrefix(const std::vector<Completion> &Comps);
virtual std::vector<Completion> getCompletions(StringRef Buffer,