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mod expr_extensions;
#[macro_use]
mod extensions;
mod generated;
mod tokens;
mod traits;
use crate::{syntax_node::SyntaxNodeChildren, SmolStr, SyntaxKind, SyntaxNode, SyntaxToken};
pub use self::{
expr_extensions::*,
extensions::{PathSegmentKind, StructKind, VisibilityKind},
generated::*,
tokens::*,
traits::*,
};
pub use abi::StructMemoryKind;
use std::marker::PhantomData;
pub trait AstNode: Clone {
fn can_cast(kind: SyntaxKind) -> bool;
fn cast(syntax: SyntaxNode) -> Option<Self>
where
Self: Sized;
fn syntax(&self) -> &SyntaxNode;
}
pub trait AstToken {
fn cast(token: SyntaxToken) -> Option<Self>
where
Self: Sized;
fn syntax(&self) -> &SyntaxToken;
fn text(&self) -> &SmolStr {
self.syntax().text()
}
}
#[derive(Debug)]
pub struct AstChildren<N> {
inner: SyntaxNodeChildren,
ph: PhantomData<N>,
}
impl<N> AstChildren<N> {
fn new(parent: &SyntaxNode) -> Self {
AstChildren {
inner: parent.children(),
ph: PhantomData,
}
}
}
impl<N: AstNode> Iterator for AstChildren<N> {
type Item = N;
fn next(&mut self) -> Option<N> {
self.inner.by_ref().find_map(N::cast)
}
}
fn child_opt<P: AstNode + ?Sized, C: AstNode>(parent: &P) -> Option<C> {
children(parent).next()
}
fn children<P: AstNode + ?Sized, C: AstNode>(parent: &P) -> AstChildren<C> {
AstChildren::new(parent.syntax())
}