Trait Printer

pub trait Printer<'tcx>: Sized {
    // Required methods
    fn tcx<'a>(&'a self) -> TyCtxt<'tcx>;
    fn print_region(&mut self, region: Region<'tcx>) -> Result<(), PrintError>;
    fn print_type(&mut self, ty: Ty<'tcx>) -> Result<(), PrintError>;
    fn print_dyn_existential(
        &mut self,
        predicates: &'tcx List<PolyExistentialPredicate<'tcx>>,
    ) -> Result<(), PrintError>;
    fn print_const(&mut self, ct: Const<'tcx>) -> Result<(), PrintError>;
    fn path_crate(&mut self, cnum: CrateNum) -> Result<(), PrintError>;
    fn path_qualified(
        &mut self,
        self_ty: Ty<'tcx>,
        trait_ref: Option<TraitRef<'tcx>>,
    ) -> Result<(), PrintError>;
    fn path_append_impl(
        &mut self,
        print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>,
        disambiguated_data: &DisambiguatedDefPathData,
        self_ty: Ty<'tcx>,
        trait_ref: Option<TraitRef<'tcx>>,
    ) -> Result<(), PrintError>;
    fn path_append(
        &mut self,
        print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>,
        disambiguated_data: &DisambiguatedDefPathData,
    ) -> Result<(), PrintError>;
    fn path_generic_args(
        &mut self,
        print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>,
        args: &[GenericArg<'tcx>],
    ) -> Result<(), PrintError>;

    // Provided methods
    fn print_def_path(
        &mut self,
        def_id: DefId,
        args: &'tcx [GenericArg<'tcx>],
    ) -> Result<(), PrintError> { ... }
    fn print_impl_path(
        &mut self,
        impl_def_id: DefId,
        args: &'tcx [GenericArg<'tcx>],
        self_ty: Ty<'tcx>,
        trait_ref: Option<TraitRef<'tcx>>,
    ) -> Result<(), PrintError> { ... }
    fn default_print_def_path(
        &mut self,
        def_id: DefId,
        args: &'tcx [GenericArg<'tcx>],
    ) -> Result<(), PrintError> { ... }
    fn default_print_impl_path(
        &mut self,
        impl_def_id: DefId,
        _args: &'tcx [GenericArg<'tcx>],
        self_ty: Ty<'tcx>,
        impl_trait_ref: Option<TraitRef<'tcx>>,
    ) -> Result<(), PrintError> { ... }
}

Interface for outputting user-facing “type-system entities” (paths, types, lifetimes, constants, etc.) as a side-effect (e.g. formatting, like PrettyPrinter implementors do) or by constructing some alternative representation (e.g. an AST), which the associated types allow passing through the methods.

For pretty-printing/formatting in particular, see PrettyPrinter.

Required Methods

fn tcx<'a>(&'a self) -> TyCtxt<'tcx>

fn print_region(&mut self, region: Region<'tcx>) -> Result<(), PrintError>

fn print_type(&mut self, ty: Ty<'tcx>) -> Result<(), PrintError>

fn print_dyn_existential( &mut self, predicates: &'tcx List<PolyExistentialPredicate<'tcx>>, ) -> Result<(), PrintError>

fn print_const(&mut self, ct: Const<'tcx>) -> Result<(), PrintError>

fn path_crate(&mut self, cnum: CrateNum) -> Result<(), PrintError>

fn path_qualified( &mut self, self_ty: Ty<'tcx>, trait_ref: Option<TraitRef<'tcx>>, ) -> Result<(), PrintError>

fn path_append_impl( &mut self, print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>, disambiguated_data: &DisambiguatedDefPathData, self_ty: Ty<'tcx>, trait_ref: Option<TraitRef<'tcx>>, ) -> Result<(), PrintError>

fn path_append( &mut self, print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>, disambiguated_data: &DisambiguatedDefPathData, ) -> Result<(), PrintError>

fn path_generic_args( &mut self, print_prefix: impl FnOnce(&mut Self) -> Result<(), PrintError>, args: &[GenericArg<'tcx>], ) -> Result<(), PrintError>

Provided Methods

fn print_def_path( &mut self, def_id: DefId, args: &'tcx [GenericArg<'tcx>], ) -> Result<(), PrintError>

fn print_impl_path( &mut self, impl_def_id: DefId, args: &'tcx [GenericArg<'tcx>], self_ty: Ty<'tcx>, trait_ref: Option<TraitRef<'tcx>>, ) -> Result<(), PrintError>

fn default_print_def_path( &mut self, def_id: DefId, args: &'tcx [GenericArg<'tcx>], ) -> Result<(), PrintError>

fn default_print_impl_path( &mut self, impl_def_id: DefId, _args: &'tcx [GenericArg<'tcx>], self_ty: Ty<'tcx>, impl_trait_ref: Option<TraitRef<'tcx>>, ) -> Result<(), PrintError>

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<'tcx> Printer<'tcx> for FmtPrinter<'_, 'tcx>