yew_macro/html_tree/
html_block.rs

1use proc_macro2::Delimiter;
2use quote::{quote, quote_spanned, ToTokens};
3use syn::buffer::Cursor;
4use syn::parse::{Parse, ParseStream};
5use syn::{braced, token};
6
7use super::{HtmlIterable, HtmlNode, ToNodeIterator};
8use crate::PeekValue;
9
10pub struct HtmlBlock {
11    pub content: BlockContent,
12    brace: token::Brace,
13}
14
15pub enum BlockContent {
16    Node(Box<HtmlNode>),
17    Iterable(Box<HtmlIterable>),
18}
19
20impl PeekValue<()> for HtmlBlock {
21    fn peek(cursor: Cursor) -> Option<()> {
22        cursor.group(Delimiter::Brace).map(|_| ())
23    }
24}
25
26impl Parse for HtmlBlock {
27    fn parse(input: ParseStream) -> syn::Result<Self> {
28        let content;
29        let brace = braced!(content in input);
30        let content = if HtmlIterable::peek(content.cursor()).is_some() {
31            BlockContent::Iterable(Box::new(content.parse()?))
32        } else {
33            BlockContent::Node(Box::new(content.parse()?))
34        };
35
36        Ok(HtmlBlock { content, brace })
37    }
38}
39
40impl ToTokens for HtmlBlock {
41    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
42        let HtmlBlock { content, .. } = self;
43        let new_tokens = match content {
44            BlockContent::Iterable(html_iterable) => quote! {#html_iterable},
45            BlockContent::Node(html_node) => quote! {#html_node},
46        };
47
48        tokens.extend(quote! {#new_tokens});
49    }
50}
51
52impl ToNodeIterator for HtmlBlock {
53    fn to_node_iterator_stream(&self) -> Option<proc_macro2::TokenStream> {
54        let HtmlBlock { content, brace } = self;
55        let new_tokens = match content {
56            BlockContent::Iterable(iterable) => iterable.to_node_iterator_stream(),
57            BlockContent::Node(node) => node.to_node_iterator_stream(),
58        }?;
59
60        Some(quote_spanned! {brace.span=> #new_tokens})
61    }
62}
yew_macro/html_tree/html_block.rs

yew_macro/html_tree/
html_block.rs
