Struct syn::Generics

pub struct Generics {
    pub lt_token: Option<Lt>,
    pub params: Punctuated<GenericParam, Comma>,
    pub gt_token: Option<Gt>,
    pub where_clause: Option<WhereClause>,
}

Lifetimes and type parameters attached to a declaration of a function, enum, trait, etc.

This type is available only if Syn is built with the "derive" or "full" feature.

Fields

lt_token: Option<Lt>

params: Punctuated<GenericParam, Comma>

gt_token: Option<Gt>

where_clause: Option<WhereClause>

Implementations

impl Generics

pub fn type_params(&self) -> TypeParams<'_>

Returns an Iterator<Item = &TypeParam> over the type parameters in self.params.

pub fn type_params_mut(&mut self) -> TypeParamsMut<'_>

Returns an Iterator<Item = &mut TypeParam> over the type parameters in self.params.

pub fn lifetimes(&self) -> Lifetimes<'_>

Returns an Iterator<Item = &LifetimeDef> over the lifetime parameters in self.params.

pub fn lifetimes_mut(&mut self) -> LifetimesMut<'_>

Returns an Iterator<Item = &mut LifetimeDef> over the lifetime parameters in self.params.

pub fn const_params(&self) -> ConstParams<'_>

Returns an Iterator<Item = &ConstParam> over the constant parameters in self.params.

pub fn const_params_mut(&mut self) -> ConstParamsMut<'_>

Returns an Iterator<Item = &mut ConstParam> over the constant parameters in self.params.

pub fn make_where_clause(&mut self) -> &mut WhereClause

Initializes an empty where-clause if there is not one present already.

impl Generics

pub fn split_for_impl(
    &self
) -> (ImplGenerics<'_>, TypeGenerics<'_>, Option<&WhereClause>)

Split a type’s generics into the pieces required for impl’ing a trait for that type.

let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
quote! {
    impl #impl_generics MyTrait for #name #ty_generics #where_clause {
        // ...
    }
}

This method is available only if Syn is built with the "derive" or "full" feature and the "printing" feature.

Trait Implementations

impl Clone for Generics

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Default for Generics

fn default() -> Self

Returns the “default value” for a type.

impl Parse for Generics

fn parse(input: ParseStream<'_>) -> Result<Self>

impl ToTokens for Generics

fn to_tokens(&self, tokens: &mut TokenStream)

Write self to the given TokenStream.

fn to_token_stream(&self) -> TokenStream

Convert self directly into a TokenStream object.

fn into_token_stream(self) -> TokenStream

Convert self directly into a TokenStream object.