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>,
}

This is supported on crate features full or derive only.

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>)

This is supported on crate feature printing only.

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

This is supported on crate feature clone-impls only.

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Generics

This is supported on crate feature extra-traits only.

fn fmt(&self, formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Generics

fn default() -> Self

Returns the “default value” for a type.

impl Eq for Generics

This is supported on crate feature extra-traits only.

impl Hash for Generics

This is supported on crate feature extra-traits only.

fn hash<H>(&self, state: &mut H) where
    H: Hasher, 

Feeds this value into the given Hasher.

pub fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl Parse for Generics

This is supported on crate feature parsing only.

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

impl PartialEq<Generics> for Generics

This is supported on crate feature extra-traits only.

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use]pub fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl ToTokens for Generics

This is supported on crate feature printing only.

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

Write self to the given TokenStream.

pub fn to_token_stream(&self) -> TokenStream

Convert self directly into a TokenStream object.

pub fn into_token_stream(self) -> TokenStream

Convert self directly into a TokenStream object.