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    },
58};
59
60/// The main trait to go from untyped `SyntaxNode`  to a typed ast. The
61/// conversion itself has zero runtime cost: ast and syntax nodes have exactly
62/// the same representation: a pointer to the tree root and a pointer to the
63/// node itself.
64pub trait AstNode {
65    fn can_cast(kind: SyntaxKind) -> bool
66    where
67        Self: Sized;
68
69    fn cast(syntax: SyntaxNode) -> Option<Self>
70    where
71        Self: Sized;
72
73    fn syntax(&self) -> &SyntaxNode;
74    fn clone_for_update(&self) -> Self
75    where
76        Self: Sized,
77    {
78        Self::cast(self.syntax().clone_for_update()).unwrap()
79    }
80    fn clone_subtree(&self) -> Self
81    where
82        Self: Sized,
83    {
84        Self::cast(self.syntax().clone_subtree()).unwrap()
85    }
86}
87
88/// Like `AstNode`, but wraps tokens rather than interior nodes.
89pub trait AstToken {
90    fn can_cast(token: SyntaxKind) -> bool
91    where
92        Self: Sized;
93
94    fn cast(syntax: SyntaxToken) -> Option<Self>
95    where
96        Self: Sized;
97
98    fn syntax(&self) -> &SyntaxToken;
99
100    fn text(&self) -> &str {
101        self.syntax().text()
102    }
103}
104
105/// An iterator over `SyntaxNode` children of a particular AST type.
106#[derive(Debug, Clone)]
107pub struct AstChildren<N> {
108    inner: SyntaxNodeChildren,
109    ph: PhantomData<N>,
110}
111
112impl<N> AstChildren<N> {
113    fn new(parent: &SyntaxNode) -> Self {
114        AstChildren {
115            inner: parent.children(),
116            ph: PhantomData,
117        }
118    }
119}
120
121impl<N: AstNode> Iterator for AstChildren<N> {
122    type Item = N;
123    fn next(&mut self) -> Option<N> {
124        self.inner.find_map(N::cast)
125    }
126}
squawk_syntax/ast.rs

squawk_syntax/
ast.rs
