wip: proc: view macro implementation

Cargo.lock

@@ -972,6 +972,15 @@ dependencies = [
  "tengri_tui",
 ]
 
+[[package]]
+name = "tengri_proc"
+version = "0.13.0"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "tengri_tui"
 version = "0.13.0"

Cargo.toml

@@ -1,5 +1,6 @@
 [workspace.package]
 version = "0.13.0"
+edition = "2024"
 
 [workspace]
 resolver = "2"
@@ -8,7 +9,8 @@ members = [
   "./input",
   "./output",
   "./tui",
-  "./dsl"
+  "./dsl",
+  "./proc",
 ]
 
 [profile.release]

dsl/Cargo.toml

@@ -1,8 +1,8 @@
 [package]
 name        = "tengri_dsl"
-edition     = "2024"
 description = "UI metaframework, tiny S-expression-based DSL."
 version     = { workspace = true }
+edition     = { workspace = true }
 
 [dependencies]
 konst     = { version = "0.3.16", features = [ "rust_1_83" ] }

input/Cargo.toml

@@ -1,8 +1,8 @@
 [package]
 name        = "tengri_input"
-edition     = "2024"
 description = "UI metaframework, input layer."
 version     = { workspace = true }
+edition     = { workspace = true }
 
 [dependencies]
 tengri_dsl = { optional = true, path = "../dsl" }

output/Cargo.toml

@@ -1,8 +1,8 @@
 [package]
 name        = "tengri_output"
-edition     = "2024"
 description = "UI metaframework, output layer."
 version     = { workspace = true }
+edition     = { workspace = true }
 
 [dependencies]
 tengri_dsl = { optional = true, path = "../dsl" }

proc/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name        = "tengri_proc"
+description = "UI metaframework, procedural macros."
+version     = { workspace = true }
+edition     = { workspace = true }
+
+[lib]
+proc-macro = true
+
+[dependencies]
+syn = { version = "2", features = ["full"] }
+quote = { version = "1" }
+proc-macro2 = { version = "1", features = ["span-locations"] }

proc/src/lib.rs

@@ -0,0 +1,26 @@
+extern crate proc_macro;
+use proc_macro::TokenStream;
+use proc_macro2::{TokenStream as TokenStream2};
+
+mod proc_view;
+
+#[proc_macro_attribute]
+pub fn view (meta: TokenStream, item: TokenStream) -> TokenStream {
+    self::proc_view::view_impl(meta.into(), item.into()).into()
+    //for attr in syn::parse_macro_input!(meta as syn::MetaList).iter() {
+    //}
+    //let item = syn::parse_macro_input!(item as syn::ItemImpl);
+    //let output = "TuiOut";
+    //let target = "Tek";
+    //let define = "self.config.view";
+    //let expose = vec![];
+    //let output = format!(
+        //"::tengri_dsl::view!({}:|self:{}|self.size.of(::tengri_dsl::View(self,{}));{{{}}});",
+        //output,
+        //target,
+        //define,
+        //expose.iter().fold(String::new(), |acc, (key, value)|format!("{acc},{key}=>{value}")),
+    //);
+    //let output = "";
+    //output.parse().unwrap()
+}

proc/src/proc_view.rs

@@ -0,0 +1,120 @@
+use proc_macro::TokenStream;
+use proc_macro2::{TokenStream as TokenStream2, TokenTree, Ident};
+use syn::parse_macro_input;
+use syn::{Expr, Attribute, Meta, MetaList, Path, PathSegment, PathArguments, ImplItem};
+use syn::parse::{Parse, ParseStream, Result};
+use syn::token::PathSep;
+use syn::punctuated::Punctuated;
+
+pub(crate) fn view_impl (meta: TokenStream, item: TokenStream) -> TokenStream {
+    let ViewMeta { output, define, attrs, .. } = parse_macro_input!(meta as ViewMeta);
+    let ViewItem { target, mapped, items, .. } = parse_macro_input!(item as ViewItem);
+    quote::quote! {
+        #(#attrs)*
+        impl #target {
+            #(#items)*
+        }
+        /// Generated by [tengri_proc].
+        impl ::tengri::Content<#output> for #target {
+            fn content (&self) -> impl Render<#output> {
+                self.size.of(::tengri::View(self, #define))
+            }
+        }
+        /// Generated by [tengri_proc].
+        impl<'a> ::tengri::ViewContext<'a, #output> for #target {
+            fn get_content_sym (&'a self, value: &Value<'a>) -> Option<RenderBox<'a, #output>> {
+                match value {
+                    #mapped
+                    _ => panic!("expected Sym(content), got: {value:?}")
+                }
+                //if let Value::Sym(s) = value {
+                    //match *s {
+                        //$($sym => Some($body.boxed()),)*
+                        //_ => None
+                    //}
+                //} else {
+                    //panic!("expected Sym(content), got: {value:?}")
+                //}
+            }
+        }
+    }.into()
+}
+
+struct ViewMeta {
+    attrs:  Vec<Attribute>,
+    output: Option<Ident>,
+    define: Expr,
+}
+
+impl Parse for ViewMeta {
+    fn parse (input: ParseStream) -> Result<Self> {
+        let mut output = None;
+        let mut define = None;
+        let mut attrs  = input.call(Attribute::parse_outer)?.into_iter().filter(|attr| {
+            if let Attribute { meta: Meta::List(MetaList { path, tokens, .. }), .. } = attr
+                && path.segments.len() == 2
+                && nth_segment_is(&path.segments, 0, "tengri")
+                && nth_segment_is(&path.segments, 1, "view")
+                && let Some(TokenTree::Group(group)) = tokens.clone().into_iter().next()
+                && let Some(TokenTree::Ident(ident)) = group.stream().into_iter().next()
+            {
+                output = Some(ident);
+                return false
+            }
+            true
+        }).collect();
+
+        if let Some(define) = define {
+            Ok(Self { attrs, output, define })
+        } else {
+            Err(input.error("Missing view definition."))
+        }
+    }
+}
+
+fn nth_segment_is (segments: &Punctuated<PathSegment, PathSep>, n: usize, x: &str) -> bool {
+    if let Some(PathSegment { arguments: PathArguments::None, ident, .. }) = segments.get(n) {
+        if format!("{ident}") != x {
+            return true
+        }
+    }
+    return false
+}
+
+struct ViewItem {
+    items:  Vec<ImplItem>,
+    target: &'static str,
+    mapped: &'static str,
+}
+
+impl Parse for ViewItem {
+    fn parse (input: ParseStream) -> Result<Self> {
+        let items = vec![];
+        Ok(Self {
+            items,
+            target: "",
+            mapped: "",
+        })
+    }
+}
+
+#[cfg(test)] #[test] fn test_view () {
+
+    use syn::{ItemImpl, parse_quote};
+
+    let _: ItemImpl = parse_quote! {
+        #[tengri::view(Tui)]
+        impl SomeView {
+            #[tengri::view]
+            fn view (&self) -> impl Content<TuiOut> + use<'_> {
+                "view-1"
+            }
+
+            #[tengri::view(":view-1")]
+            fn view_1 (&self) -> impl Content<TuiOut> + use<'_> {
+                "view-1"
+            }
+        }
+    };
+
+}

tui/Cargo.toml

@@ -1,8 +1,8 @@
 [package]
 name        = "tengri_tui"
-edition     = "2024"
 description = "UI metaframework, Ratatui backend."
 version     = { workspace = true }
+edition     = { workspace = true }
 
 [dependencies]
 palette       = { version = "0.7.6", features = [ "random" ] }