Files
dioxus/packages/rsx/src/lib.rs
T
2022-05-25 08:58:59 -05:00

101 lines
2.8 KiB
Rust

//! Parse the root tokens in the rsx!{} macro
//! =========================================
//!
//! This parsing path emerges directly from the macro call, with `RsxRender` being the primary entrance into parsing.
//! This feature must support:
//! - [x] Optionally rendering if the `in XYZ` pattern is present
//! - [x] Fragments as top-level element (through ambiguous)
//! - [x] Components as top-level element (through ambiguous)
//! - [x] Tags as top-level elements (through ambiguous)
//! - [x] Good errors if parsing fails
//!
//! Any errors in using rsx! will likely occur when people start using it, so the first errors must be really helpful.
#[macro_use]
mod errors;
mod component;
mod element;
mod ifmt;
mod node;
// Re-export the namespaces into each other
pub use component::*;
pub use element::*;
pub use ifmt::*;
pub use node::*;
// imports
use proc_macro2::TokenStream as TokenStream2;
use quote::{quote, ToTokens, TokenStreamExt};
use syn::{
parse::{Parse, ParseStream},
Ident, Result, Token,
};
pub struct CallBody {
pub custom_context: Option<Ident>,
pub roots: Vec<BodyNode>,
}
impl Parse for CallBody {
fn parse(input: ParseStream) -> Result<Self> {
let custom_context = if input.peek(Ident) && input.peek2(Token![,]) {
let name = input.parse::<Ident>()?;
input.parse::<Token![,]>()?;
Some(name)
} else {
None
};
let mut roots = Vec::new();
while !input.is_empty() {
let node = input.parse::<BodyNode>()?;
if input.peek(Token![,]) {
let _ = input.parse::<Token![,]>();
}
roots.push(node);
}
Ok(Self {
custom_context,
roots,
})
}
}
/// Serialize the same way, regardless of flavor
impl ToTokens for CallBody {
fn to_tokens(&self, out_tokens: &mut TokenStream2) {
let inner = if self.roots.len() == 1 {
let inner = &self.roots[0];
quote! { #inner }
} else {
let childs = &self.roots;
quote! { __cx.fragment_root([ #(#childs),* ]) }
};
match &self.custom_context {
// The `in cx` pattern allows directly rendering
Some(ident) => out_tokens.append_all(quote! {
#ident.render(LazyNodes::new(move |__cx: NodeFactory| -> VNode {
use dioxus_elements::{GlobalAttributes, SvgAttributes};
#inner
}))
}),
// Otherwise we just build the LazyNode wrapper
None => out_tokens.append_all(quote! {
LazyNodes::new(move |__cx: NodeFactory| -> VNode {
use dioxus_elements::{GlobalAttributes, SvgAttributes};
#inner
})
}),
};
}
}