compose_syntax/ast/
bindings.rs

1use crate::ast::func::Pattern;
2use crate::ast::{node, AstNode, Expr, Ident};
3use crate::kind::SyntaxKind;
4use crate::{Span, SyntaxNode};
5
6node! {
7    struct LetBinding
8}
9
10impl<'a> LetBinding<'a> {
11    pub fn has_initial_value(self) -> bool {
12        self.0.children().any(|n| n.kind() == SyntaxKind::Eq)
13    }
14    
15    pub fn initial_value(self) -> Option<Expr<'a>> {
16        self.0.children().filter_map(SyntaxNode::cast).nth(1)
17    }
18    
19    fn bindings(self) -> Vec<Ident<'a>> {
20        let pattern: Pattern = self.0.try_cast_first().expect("expected pattern");
21        pattern.bindings()
22    }
23    
24    pub fn pattern(self) -> Pattern<'a> {
25        self.0.cast_first()
26    }
27
28    pub fn is_mut(self) -> bool {
29        self.0.children().any(|n| n.kind() == SyntaxKind::Mut)
30    }
31    
32    pub fn eq_span(self) -> Span {
33        self.0.children().find(|&n| n.kind() == SyntaxKind::Eq).map(|n| n.span()).unwrap_or_else(|| self.0.span())
34    }
35    
36    pub fn mut_span(self) -> Option<Span> {
37        self.0.children().find(|&n| n.kind() == SyntaxKind::Mut).map(|n| n.span())
38    }
39    
40    pub fn initial_value_span(self) -> Option<Span> {
41        self.initial_value().map(|e| e.span())
42    }
43
44    pub fn is_public(self) -> bool {
45        self.0.children().any(|n| n.kind() == SyntaxKind::Pub)
46    }
47
48    pub fn pub_span(self) -> Option<Span> {
49        self.0.children().find(|&n| n.kind() == SyntaxKind::Pub).map(|n| n.span())
50    }
51}
52
53
54#[cfg(test)]
55mod tests {
56    use super::*;
57    use crate::assert_ast;
58    use crate::ast::Int;
59
60    #[test]
61    fn test_let_binding() {
62        assert_ast!(
63            "let x = 1",
64            binding as LetBinding {
65                binding.bindings().into_iter() => [
66                    ident as Ident {
67                        assert_eq!(ident.get(), "x");
68                    }
69                ]
70                with init: Int = binding.initial_value().unwrap() => {
71                    assert_eq!(init.get(), 1);
72                }
73            }
74        )
75    }
76}
compose_syntax/ast/bindings.rs

compose_syntax/ast/
bindings.rs
