rune/ast/
fields.rs

1use core::iter;
2use core::slice;
3
4use crate::ast::prelude::*;
5
6/// An item body declaration.
7#[derive(Debug, TryClone, PartialEq, Eq, ToTokens, OptionSpanned)]
8#[non_exhaustive]
9pub enum Fields {
10    /// A regular body.
11    Named(ast::Braced<ast::Field, T![,]>),
12    /// A tuple body.
13    Unnamed(ast::Parenthesized<ast::Field, T![,]>),
14    /// An empty body.
15    Empty,
16}
17
18impl Fields {
19    /// If the body needs to be terminated with a semicolon.
20    pub(crate) fn needs_semi_colon(&self) -> bool {
21        matches!(self, Self::Empty | Self::Unnamed(..))
22    }
23}
24
25impl Parse for Fields {
26    fn parse(p: &mut Parser<'_>) -> Result<Self> {
27        Ok(match p.nth(0)? {
28            K!['('] => Self::Unnamed(p.parse()?),
29            K!['{'] => Self::Named(p.parse()?),
30            _ => Self::Empty,
31        })
32    }
33}
34
35type ToField = fn(&(ast::Field, Option<T![,]>)) -> &ast::Field;
36
37fn to_field((field, _): &(ast::Field, Option<T![,]>)) -> &ast::Field {
38    field
39}
40
41impl<'a> IntoIterator for &'a Fields {
42    type Item = &'a ast::Field;
43    type IntoIter = iter::Map<slice::Iter<'a, (ast::Field, Option<T![,]>)>, ToField>;
44
45    fn into_iter(self) -> Self::IntoIter {
46        static STATIC: &[(ast::Field, Option<T![,]>); 0] = &[];
47
48        match self {
49            Fields::Named(fields) => fields.iter().map(to_field as ToField),
50            Fields::Unnamed(fields) => fields.iter().map(to_field as ToField),
51            Fields::Empty => STATIC.iter().map(to_field as ToField),
52        }
53    }
54}
rune/ast/fields.rs

rune/ast/
fields.rs
