squawk_syntax/
ast.rs

1// via https://github.com/rust-lang/rust-analyzer/blob/d8887c0758bbd2d5f752d5bd405d4491e90e7ed6/crates/syntax/src/ast.rs
2//
3// Permission is hereby granted, free of charge, to any
4// person obtaining a copy of this software and associated
5// documentation files (the "Software"), to deal in the
6// Software without restriction, including without
7// limitation the rights to use, copy, modify, merge,
8// publish, distribute, sublicense, and/or sell copies of
9// the Software, and to permit persons to whom the Software
10// is furnished to do so, subject to the following
11// conditions:
12//
13// The above copyright notice and this permission notice
14// shall be included in all copies or substantial portions
15// of the Software.
16//
17// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
18// ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
19// TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
20// PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
21// SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
22// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
23// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
24// IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
25// DEALINGS IN THE SOFTWARE.
26
27mod generated;
28mod node_ext;
29mod nodes;
30mod support;
31mod traits;
32
33use std::marker::PhantomData;
34
35use crate::syntax_node::{SyntaxNode, SyntaxNodeChildren, SyntaxToken};
36use squawk_parser::SyntaxKind;
37
38pub use self::{
39    // generated::{nodes::*, tokens::*},
40    generated::tokens::*,
41    nodes::*,
42    // node_ext::{
43    //     AttrKind, FieldKind, Macro, NameLike, NameOrNameRef, PathSegmentKind, SelfParamKind,
44    //     SlicePatComponents, StructKind, TraitOrAlias, TypeBoundKind, TypeOrConstParam,
45    //     VisibilityKind,
46    // },
47    // operators::{ArithOp, BinaryOp, CmpOp, LogicOp, Ordering, RangeOp, UnaryOp},
48    // token_ext::{CommentKind, CommentPlacement, CommentShape, IsString, QuoteOffsets, Radix},
49    traits::{
50        // AttrDocCommentIter, DocCommentIter,
51        HasArgList, // HasAttrs, HasDocComments, HasGenericArgs,
52        HasIfExists,
53        HasIfNotExists, // HasTypeBounds,
54        // HasVisibility,
55        // HasGenericParams, HasLoopBody,
56        HasName,
57        HasParamList,
58        NameLike,
59    },
60};
61
62/// The main trait to go from untyped `SyntaxNode`  to a typed ast. The
63/// conversion itself has zero runtime cost: ast and syntax nodes have exactly
64/// the same representation: a pointer to the tree root and a pointer to the
65/// node itself.
66pub trait AstNode {
67    fn can_cast(kind: SyntaxKind) -> bool
68    where
69        Self: Sized;
70
71    fn cast(syntax: SyntaxNode) -> Option<Self>
72    where
73        Self: Sized;
74
75    fn syntax(&self) -> &SyntaxNode;
76    fn clone_for_update(&self) -> Self
77    where
78        Self: Sized,
79    {
80        Self::cast(self.syntax().clone_for_update()).unwrap()
81    }
82    fn clone_subtree(&self) -> Self
83    where
84        Self: Sized,
85    {
86        Self::cast(self.syntax().clone_subtree()).unwrap()
87    }
88}
89
90/// Like `AstNode`, but wraps tokens rather than interior nodes.
91pub trait AstToken {
92    fn can_cast(token: SyntaxKind) -> bool
93    where
94        Self: Sized;
95
96    fn cast(syntax: SyntaxToken) -> Option<Self>
97    where
98        Self: Sized;
99
100    fn syntax(&self) -> &SyntaxToken;
101
102    fn text(&self) -> &str {
103        self.syntax().text()
104    }
105}
106
107/// An iterator over `SyntaxNode` children of a particular AST type.
108#[derive(Debug, Clone)]
109pub struct AstChildren<N> {
110    inner: SyntaxNodeChildren,
111    ph: PhantomData<N>,
112}
113
114impl<N> AstChildren<N> {
115    fn new(parent: &SyntaxNode) -> Self {
116        AstChildren {
117            inner: parent.children(),
118            ph: PhantomData,
119        }
120    }
121}
122
123impl<N: AstNode> Iterator for AstChildren<N> {
124    type Item = N;
125    fn next(&mut self) -> Option<N> {
126        self.inner.find_map(N::cast)
127    }
128}
squawk_syntax/ast.rs

squawk_syntax/
ast.rs
