1 //! Many kinds of items or constructs can have generic parameters: functions,
2 //! structs, impls, traits, etc. This module provides a common HIR for these
3 //! generic parameters. See also the `Generics` type and the `generics_of` query
8 use ra_syntax::ast::{self, NameOwner, TypeParamsOwner};
10 use crate::{db::PersistentHirDatabase, Name, AsName, Function, Struct, Enum, Trait, Type, ImplBlock};
12 /// Data about a generic parameter (to a function, struct, impl, ...).
13 #[derive(Clone, PartialEq, Eq, Debug)]
14 pub struct GenericParam {
15 // TODO: give generic params proper IDs
17 pub(crate) name: Name,
20 /// Data about the generic parameters of a function, struct, impl, etc.
21 #[derive(Clone, PartialEq, Eq, Debug, Default)]
22 pub struct GenericParams {
23 pub(crate) parent_params: Option<Arc<GenericParams>>,
24 pub(crate) params: Vec<GenericParam>,
27 #[derive(Clone, Copy, PartialEq, Eq, Debug, Hash)]
36 impl_froms!(GenericDef: Function, Struct, Enum, Trait, Type, ImplBlock);
39 pub(crate) fn generic_params_query(
40 db: &impl PersistentHirDatabase,
42 ) -> Arc<GenericParams> {
43 let mut generics = GenericParams::default();
44 let parent = match def {
45 GenericDef::Function(it) => it.impl_block(db),
46 GenericDef::Type(it) => it.impl_block(db),
47 GenericDef::Struct(_) | GenericDef::Enum(_) | GenericDef::Trait(_) => None,
48 GenericDef::ImplBlock(_) => None,
50 generics.parent_params = parent.map(|p| p.generic_params(db));
51 let start = generics.parent_params.as_ref().map(|p| p.params.len()).unwrap_or(0) as u32;
53 GenericDef::Function(it) => generics.fill(&*it.source(db).1, start),
54 GenericDef::Struct(it) => generics.fill(&*it.source(db).1, start),
55 GenericDef::Enum(it) => generics.fill(&*it.source(db).1, start),
56 GenericDef::Trait(it) => generics.fill(&*it.source(db).1, start),
57 GenericDef::Type(it) => generics.fill(&*it.source(db).1, start),
58 GenericDef::ImplBlock(it) => generics.fill(&*it.source(db).1, start),
64 fn fill(&mut self, node: &impl TypeParamsOwner, start: u32) {
65 if let Some(params) = node.type_param_list() {
66 self.fill_params(params, start)
70 fn fill_params(&mut self, params: &ast::TypeParamList, start: u32) {
71 for (idx, type_param) in params.type_params().enumerate() {
72 let name = type_param.name().map(AsName::as_name).unwrap_or_else(Name::missing);
73 let param = GenericParam { idx: idx as u32 + start, name };
74 self.params.push(param);
78 pub(crate) fn find_by_name(&self, name: &Name) -> Option<&GenericParam> {
79 self.params.iter().find(|p| &p.name == name)
82 pub fn count_parent_params(&self) -> usize {
83 self.parent_params.as_ref().map(|p| p.count_params_including_parent()).unwrap_or(0)
86 pub fn count_params_including_parent(&self) -> usize {
87 let parent_count = self.count_parent_params();
88 parent_count + self.params.len()
91 fn for_each_param<'a>(&'a self, f: &mut impl FnMut(&'a GenericParam)) {
92 if let Some(parent) = &self.parent_params {
93 parent.for_each_param(f);
95 self.params.iter().for_each(f);
98 pub fn params_including_parent(&self) -> Vec<&GenericParam> {
99 let mut vec = Vec::with_capacity(self.count_params_including_parent());
100 self.for_each_param(&mut |p| vec.push(p));