wip: proc: simplify expose macro

Cargo.lock

@@ -976,7 +976,6 @@ dependencies = [
 name = "tengri_proc"
 version = "0.13.0"
 dependencies = [
- "heck",
  "proc-macro2",
  "quote",
  "syn",

proc/src/lib.rs

@@ -2,7 +2,6 @@ extern crate proc_macro;
 
 pub(crate) use std::collections::{BTreeMap, BTreeSet};
 pub(crate) use std::cmp::Ordering;
-pub(crate) use std::sync::Arc;
 pub(crate) use proc_macro::TokenStream;
 pub(crate) use proc_macro2::{
     TokenStream as TokenStream2, TokenTree,
@@ -11,48 +10,39 @@ pub(crate) use proc_macro2::{
 pub(crate) use syn::{
     parse, parse_macro_input, parse_quote as pq,
     braced, bracketed, parenthesized, Token,
-    Arm, Expr, Attribute, Meta, MetaList, Path, PathSegment, PathArguments,
-    ImplItem, ImplItemFn, LitStr, Type, ItemImpl, ReturnType, Signature, FnArg, PatType,
+    Arm, Expr, Attribute, Meta, MetaList, Path, PathSegment, PathArguments, ImplItem, LitStr, Type,
     parse::{Parse, ParseStream, Result},
     token::{PathSep, Brace},
     punctuated::Punctuated,
 };
 pub(crate) use quote::{quote, TokenStreamExt, ToTokens};
-pub(crate) use heck::{AsKebabCase, AsUpperCamelCase};
 
 mod proc_view;
 mod proc_expose;
-mod proc_command;
 
 #[proc_macro_attribute]
 pub fn view (meta: TokenStream, item: TokenStream) -> TokenStream {
-    use self::proc_view::{ViewDef, ViewMeta, ViewImpl};
-    write_macro(ViewDef(
+    use self::proc_view::{ViewDefinition, ViewMeta, ViewImpl};
+    write_macro(ViewDefinition(
         parse_macro_input!(meta as ViewMeta),
-        parse_macro_input!(item as ViewImpl),
+        parse_macro_input!(data as ViewImpl),
     ))
 }
 
 #[proc_macro_attribute]
 pub fn expose (meta: TokenStream, item: TokenStream) -> TokenStream {
-    use self::proc_expose::{ExposeDef, ExposeMeta, ExposeImpl};
-    write_macro(ExposeDef(
+    use self::proc_view::{ExposeDefinition, ExposeMeta, ExposeImpl};
+    write_macro(ExposeDefinition(
         parse_macro_input!(meta as ExposeMeta),
-        parse_macro_input!(item as ExposeImpl),
-    ))
-}
-
-#[proc_macro_attribute]
-pub fn command (meta: TokenStream, item: TokenStream) -> TokenStream {
-    use self::proc_command::{CommandDef, CommandMeta, CommandImpl};
-    write_macro(CommandDef(
-        parse_macro_input!(meta as CommandMeta),
-        parse_macro_input!(item as CommandImpl),
+        parse_macro_input!(data as ExposeImpl),
     ))
 }
 
 fn write_macro <T: ToTokens> (t: T) -> TokenStream {
     let mut out = TokenStream2::new();
-    t.to_tokens(&mut out);
+    self::proc_expose::ExposeDefinition(
+        parse_macro_input!(meta as ExposeMeta),
+        parse_macro_input!(data as ExposeImpl),
+    ).to_tokens(&mut out);
     out.into()
 }

proc/src/proc_command.rs

@@ -1,144 +0,0 @@
-use crate::*;
-
-#[derive(Debug, Clone)]
-pub(crate) struct CommandDef(pub(crate) CommandMeta, pub(crate) CommandImpl);
-
-#[derive(Debug, Clone)]
-pub(crate) struct CommandMeta {
-    target: Ident,
-}
-
-#[derive(Debug, Clone)]
-pub(crate) struct CommandImpl(ItemImpl, BTreeMap<Arc<str>, CommandArm>);
-
-#[derive(Debug, Clone)]
-struct CommandVariant(Ident, Vec<FnArg>);
-
-#[derive(Debug, Clone)]
-struct CommandArm(Arc<str>, Ident, Vec<FnArg>, ReturnType);
-
-impl Parse for CommandMeta {
-    fn parse (input: ParseStream) -> Result<Self> {
-        Ok(Self {
-            target: input.parse::<Ident>()?,
-        })
-    }
-}
-
-impl Parse for CommandImpl {
-    fn parse (input: ParseStream) -> Result<Self> {
-        let block = input.parse::<ItemImpl>()?;
-        let mut exposed: BTreeMap<Arc<str>, CommandArm> = Default::default();
-        for item in block.items.iter() {
-            if let ImplItem::Fn(ImplItemFn {
-                sig: Signature { ident, inputs, output, .. }, ..
-            }) = item {
-                let key: Arc<str> =
-                    format!("{}", AsKebabCase(format!("{}", &ident))).into();
-                let variant: Arc<str> =
-                    format!("{}", AsUpperCamelCase(format!("{}", &ident))).into();
-                if exposed.contains_key(&key) {
-                    return Err(input.error(format!("already defined: {ident}")));
-                }
-                exposed.insert(key, CommandArm(
-                    variant,
-                    ident.clone(),
-                    inputs.iter().map(|x|x.clone()).collect(),
-                    output.clone(),
-                ));
-            }
-        }
-        Ok(Self(block, exposed))
-    }
-}
-
-impl ToTokens for CommandDef {
-    fn to_tokens (&self, out: &mut TokenStream2) {
-        let Self(CommandMeta { target }, CommandImpl(block, exposed)) = self;
-        let enumeration = &block.self_ty;
-        let definitions = exposed.values().map(|x|CommandVariant(
-            x.1.clone(),
-            x.2.clone(),
-        ));
-        let implementations = exposed.values().map(|x|CommandArm(
-            x.0.clone(),
-            x.1.clone(),
-            x.2.clone(),
-            x.3.clone(),
-        ));
-        for token in quote! {
-            #block
-            enum #enumeration {
-                #(#definitions)*
-            }
-            impl Command<#target> for #enumeration {
-                fn execute (self, state: &mut #target) -> Perhaps<Self> {
-                    match self {
-                        #(#implementations)*
-                    }
-                }
-            }
-        } {
-            out.append(token)
-        }
-    }
-}
-
-impl ToTokens for CommandVariant {
-    fn to_tokens (&self, out: &mut TokenStream2) {
-        let Self(ident, args) = self;
-        out.append(LitStr::new(&format!("{}", ident), Span::call_site())
-            .token());
-        out.append(Group::new(Delimiter::Parenthesis, {
-            let mut out = TokenStream2::new();
-            for arg in args.iter() {
-                if let FnArg::Typed(PatType { attrs, pat, colon_token, ty }) = arg {
-                    out.append(LitStr::new(
-                        &format!("{}", quote! { #ty }),
-                        Span::call_site()
-                    ).token());
-                    out.append(Punct::new(',', Alone));
-                }
-            }
-            out
-        }));
-        out.append(Punct::new(',', Alone));
-    }
-}
-
-impl ToTokens for CommandArm {
-    fn to_tokens (&self, out: &mut TokenStream2) {
-        let Self(symbol, ident, args, returnType) = self;
-        out.append(Punct::new(':', Joint));
-        out.append(Punct::new(':', Alone));
-        out.append(Ident::new("tengri", Span::call_site()));
-        out.append(Punct::new(':', Joint));
-        out.append(Punct::new(':', Alone));
-        out.append(Ident::new("dsl", Span::call_site()));
-        out.append(Punct::new(':', Joint));
-        out.append(Punct::new(':', Alone));
-        out.append(Ident::new("Value", Span::call_site()));
-        out.append(Punct::new(':', Joint));
-        out.append(Punct::new(':', Alone));
-        out.append(Ident::new("Sym", Span::call_site()));
-        out.append(Group::new(Delimiter::Parenthesis, {
-            let mut out = TokenStream2::new();
-            for arg in args.iter() {
-                out.append(LitStr::new(&symbol, Span::call_site()).token());
-            }
-            out
-        }));
-        out.append(Punct::new('=', Joint));
-        out.append(Punct::new('>', Alone));
-        out.append(LitStr::new(&format!("{}", ident), Span::call_site()).token());
-        out.append(Group::new(Delimiter::Parenthesis, {
-            let mut out = TokenStream2::new();
-            for arg in args.iter() {
-                // TODO
-                //out.append(LitStr::new(&symbol, Span::call_site()).token());
-            }
-            out
-        }));
-        out.append(Punct::new(',', Alone));
-    }
-}

proc/src/proc_expose.rs

@@ -1,7 +1,8 @@
 use crate::*;
+use syn::parse::discouraged::Speculative;
 
 #[derive(Debug, Clone)]
-pub(crate) struct ExposeDef(pub(crate) ExposeMeta, pub(crate) ExposeImpl);
+pub(crate) struct ExposeDefinition(pub(crate) ExposeMeta, pub(crate) ExposeImpl);
 
 #[derive(Debug, Clone)]
 pub(crate) struct ExposeMeta;
@@ -9,11 +10,14 @@ pub(crate) struct ExposeMeta;
 #[derive(Debug, Clone)]
 pub(crate) struct ExposeImpl {
     block: ItemImpl,
-    exposed: BTreeMap<ExposeType, BTreeMap<String, Ident>>,
+    exposed: BTreeMap<ExposeType, BTreeMap<ExposeSym, ExposeArm>>,
 }
 
 #[derive(Debug, Clone)]
-struct ExposeArm(String, Ident);
+struct ExposeArm {
+    key: ExposeSym,
+    value: Expr
+}
 
 #[derive(Debug, Clone)]
 struct ExposeSym(LitStr);
@@ -30,17 +34,17 @@ impl Parse for ExposeMeta {
 impl Parse for ExposeImpl {
     fn parse (input: ParseStream) -> Result<Self> {
         let block = input.parse::<ItemImpl>()?;
-        let mut exposed: BTreeMap<ExposeType, BTreeMap<String, Ident>> = Default::default();
+        let mut exposed: BTreeMap<ExposeType, BTreeMap<ExposeSym, ExposeArm>> = Default::default();
         for item in block.items.iter() {
             if let ImplItem::Fn(ImplItemFn { sig: Signature { ident, output, .. }, .. }) = item {
                 if let ReturnType::Type(_, return_type) = output {
                     let return_type = ExposeType(return_type.clone());
-                    if !exposed.contains_key(&return_type) {
-                        exposed.insert(return_type.clone(), Default::default());
+                    if !exposed.contains_key(return_type) {
+                        exposed.insert(return_type.clone(), Default::default())
                     }
                     let values = exposed.get_mut(&return_type).unwrap();
-                    let key = format!(":{}", AsKebabCase(format!("{}", &ident)));
-                    if values.contains_key(&key) {
+                    let key = format!(":{}", AsKebabCase(&ident));
+                    if values.contains_key(key) {
                         return Err(input.error(format!("already defined: {key}")))
                     }
                     values.insert(key, ident.clone());
@@ -53,9 +57,9 @@ impl Parse for ExposeImpl {
     }
 }
 
-impl ToTokens for ExposeDef {
+impl ToTokens for ExposeDefinition {
     fn to_tokens (&self, out: &mut TokenStream2) {
-        let Self(meta, data) = self;
+        let Self { meta, data } = self;
         for token in quote! { #data } {
             out.append(token)
         }
@@ -64,12 +68,11 @@ impl ToTokens for ExposeDef {
 
 impl ToTokens for ExposeImpl {
     fn to_tokens (&self, out: &mut TokenStream2) {
-        let Self { block, exposed } = self;
-        let target = &self.block.self_ty;
-        for token in quote! { #block } {
+        let Self { target, items, types } = self;
+        for token in quote! { impl #target { #(#items)* } } {
             out.append(token);
         }
-        for (t, variants) in exposed.iter() {
+        for (t, variants) in types.iter() {
             let predefined = match format!("{}", quote! { #t }).as_str() {
                 "bool" => vec![
                     quote! { ::tengri::dsl::Value::Sym(":true")  => true  },
@@ -102,7 +105,7 @@ impl ToTokens for ExposeImpl {
 
 impl ToTokens for ExposeArm {
     fn to_tokens (&self, out: &mut TokenStream2) {
-        let Self(key, value) = self;
+        let Self { key, value } = self;
         out.append(Punct::new(':', Joint));
         out.append(Punct::new(':', Alone));
         out.append(Ident::new("tengri", Span::call_site()));
@@ -117,7 +120,7 @@ impl ToTokens for ExposeArm {
         out.append(Ident::new("Sym", Span::call_site()));
         out.append(Group::new(Delimiter::Parenthesis, {
             let mut out = TokenStream2::new();
-            out.append(LitStr::new(&key, Span::call_site()).token());
+            out.append(key.0.token());
             out
         }));
         out.append(Punct::new('=', Joint));
@@ -162,7 +165,7 @@ impl Eq for ExposeSym {}
 
 impl From<Type> for ExposeType {
     fn from (this: Type) -> Self {
-        Self(Box::new(this))
+        Self(this)
     }
 }
 

proc/src/proc_view.rs

@@ -1,7 +1,7 @@
 use crate::*;
 
 #[derive(Debug, Clone)]
-pub(crate) struct ViewDef(pub(crate) ViewMeta, pub(crate) ViewImpl);
+pub(crate) struct ViewDefinition(pub(crate) ViewMeta, pub(crate) ViewImpl);
 
 #[derive(Debug, Clone)]
 pub(crate) struct ViewMeta {
@@ -11,11 +11,9 @@ pub(crate) struct ViewMeta {
 #[derive(Debug, Clone)]
 pub(crate) struct ViewImpl {
     block: ItemImpl,
-    exposed: BTreeMap<String, Ident>,
+    exposed: BTreeSet<Ident>,
 }
 
-struct ViewArm(String, Ident);
-
 impl Parse for ViewMeta {
     fn parse (input: ParseStream) -> Result<Self> {
         Ok(Self {
@@ -26,39 +24,55 @@ impl Parse for ViewMeta {
 
 impl Parse for ViewImpl {
     fn parse (input: ParseStream) -> Result<Self> {
-        let block = input.parse::<ItemImpl>()?;
-        let mut exposed: BTreeMap<String, Ident> = Default::default();
-        for item in block.items.iter() {
-            if let ImplItem::Fn(ImplItemFn { sig: Signature { ident, .. }, .. }) = item {
-                let key = format!(":{}", AsKebabCase(format!("{}", &ident)));
-                if exposed.contains_key(&key) {
-                    return Err(input.error(format!("already defined: {ident}")));
-                }
-                exposed.insert(key, ident.clone());
+        let _ = input.parse::<Token![impl]>()?;
+        let mut syms = vec![];
+        Ok(Self {
+            target: input.parse::<Ident>()?,
+            items: {
+                let group;
+                let brace = braced!(group in input);
+                let mut items = vec![];
+                while !group.is_empty() {
+                    let item = group.parse::<ViewItem>()?;
+                    if let Some(expose) = &item.expose {
+                        if let ImplItem::Fn(ref item) = item.item {
+                            let symbol = expose.clone();
+                            let name   = item.sig.ident.clone();
+                            syms.push(ViewSym { symbol, name })
+                        } else {
+                            return Err(
+                                input.error("only fn items can be exposed to #[tengri::view]")
+                            )
                         }
                     }
-        Ok(Self { block, exposed })
+                    items.push(item);
+                }
+                items
+            },
+            syms,
+        })
     }
 }
 
-impl ToTokens for ViewDef {
+impl ToTokens for ViewDefinition {
     fn to_tokens (&self, out: &mut TokenStream2) {
-        let Self(ViewMeta { output }, ViewImpl { block, exposed }) = self;
-        let ident = &block.self_ty;
-        let exposed: Vec<_> = exposed.iter().map(|(k,v)|ViewArm(k.clone(), v.clone())).collect();
+        let Self(ViewMeta { output }, ViewImpl { target, syms, items }) = self;
         for token in quote! {
-            #block
+            /// Augmented by [tengri_proc].
+            impl #target {
+                #(#items)*
+            }
             /// Generated by [tengri_proc].
-            impl ::tengri::output::Content<#output> for #ident {
+            impl ::tengri::output::Content<#output> for #target {
                 fn content (&self) -> impl Render<#output> {
                     self.size.of(::tengri::output::View(self, self.config.view))
                 }
             }
             /// Generated by [tengri_proc].
-            impl<'a> ::tengri::output::ViewContext<'a, #output> for #ident {
+            impl<'a> ::tengri::output::ViewContext<'a, #output> for #target {
                 fn get_content_sym (&'a self, value: &Value<'a>) -> Option<RenderBox<'a, #output>> {
                     match value {
-                        #(#exposed)*
+                        #(#syms)*
                         _ => panic!("expected Sym(content), got: {value:?}")
                     }
                 }
@@ -69,9 +83,8 @@ impl ToTokens for ViewDef {
     }
 }
 
-impl ToTokens for ViewArm {
+impl ToTokens for ViewSym {
     fn to_tokens (&self, out: &mut TokenStream2) {
-        let Self(key, value) = self;
         out.append(Punct::new(':', Joint));
         out.append(Punct::new(':', Alone));
         out.append(Ident::new("tengri", Span::call_site()));
@@ -86,7 +99,7 @@ impl ToTokens for ViewArm {
         out.append(Ident::new("Sym", Span::call_site()));
         out.append(Group::new(Delimiter::Parenthesis, {
             let mut out = TokenStream2::new();
-            out.append(LitStr::new(key, Span::call_site()).token());
+            out.append(self.symbol.clone());
             out
         }));
         out.append(Punct::new('=', Joint));
@@ -96,7 +109,7 @@ impl ToTokens for ViewArm {
             let mut out = TokenStream2::new();
             out.append(Ident::new("self", Span::call_site()));
             out.append(Punct::new('.', Alone));
-            out.append(value.clone());
+            out.append(self.name.clone());
             out.append(Group::new(Delimiter::Parenthesis, TokenStream2::new()));
             out.append(Punct::new('.', Alone));
             out.append(Ident::new("boxed", Span::call_site()));
@@ -107,43 +120,6 @@ impl ToTokens for ViewArm {
     }
 }
 
-//impl ToTokens for ViewSym {
-    //fn to_tokens (&self, out: &mut TokenStream2) {
-        //out.append(Punct::new(':', Joint));
-        //out.append(Punct::new(':', Alone));
-        //out.append(Ident::new("tengri", Span::call_site()));
-        //out.append(Punct::new(':', Joint));
-        //out.append(Punct::new(':', Alone));
-        //out.append(Ident::new("dsl", Span::call_site()));
-        //out.append(Punct::new(':', Joint));
-        //out.append(Punct::new(':', Alone));
-        //out.append(Ident::new("Value", Span::call_site()));
-        //out.append(Punct::new(':', Joint));
-        //out.append(Punct::new(':', Alone));
-        //out.append(Ident::new("Sym", Span::call_site()));
-        //out.append(Group::new(Delimiter::Parenthesis, {
-            //let mut out = TokenStream2::new();
-            //out.append(self.symbol.clone());
-            //out
-        //}));
-        //out.append(Punct::new('=', Joint));
-        //out.append(Punct::new('>', Alone));
-        //out.append(Ident::new("Some", Span::call_site()));
-        //out.append(Group::new(Delimiter::Parenthesis, {
-            //let mut out = TokenStream2::new();
-            //out.append(Ident::new("self", Span::call_site()));
-            //out.append(Punct::new('.', Alone));
-            //out.append(self.name.clone());
-            //out.append(Group::new(Delimiter::Parenthesis, TokenStream2::new()));
-            //out.append(Punct::new('.', Alone));
-            //out.append(Ident::new("boxed", Span::call_site()));
-            //out.append(Group::new(Delimiter::Parenthesis, TokenStream2::new()));
-            //out
-        //}));
-        //out.append(Punct::new(',', Alone));
-    //}
-//}
-
 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 {
@@ -153,17 +129,17 @@ fn nth_segment_is (segments: &Punctuated<PathSegment, PathSep>, n: usize, x: &st
     return false
 }
 
-//impl std::cmp::PartialEq for ViewItem {
-    //fn eq (&self, other: &Self) -> bool {
-        //self.item == other.item && (format!("{:?}", self.expose) == format!("{:?}", other.expose))
-    //}
-//}
+impl std::cmp::PartialEq for ViewItem {
+    fn eq (&self, other: &Self) -> bool {
+        self.item == other.item && (format!("{:?}", self.expose) == format!("{:?}", other.expose))
+    }
+}
 
-//impl std::cmp::PartialEq for ViewSym {
-    //fn eq (&self, other: &Self) -> bool {
-        //self.name == other.name && (format!("{}", self.symbol) == format!("{}", other.symbol))
-    //}
-//}
+impl std::cmp::PartialEq for ViewSym {
+    fn eq (&self, other: &Self) -> bool {
+        self.name == other.name && (format!("{}", self.symbol) == format!("{}", other.symbol))
+    }
+}
 
 #[cfg(test)] #[test] fn test_view_meta () {
     let x: ViewMeta   = pq! { SomeOutput };
@@ -172,7 +148,6 @@ fn nth_segment_is (segments: &Punctuated<PathSegment, PathSep>, n: usize, x: &st
 }
 
 #[cfg(test)] #[test] fn test_view_impl () {
-    // TODO
     let x: ViewImpl = pq! {
         impl Foo {
             /// docstring1
@@ -184,20 +159,20 @@ fn nth_segment_is (segments: &Punctuated<PathSegment, PathSep>, n: usize, x: &st
         }
     };
     let expected_target: Ident = pq! { Foo };
-    //assert_eq!(x.target, expected_target);
-    //assert_eq!(x.items.len(), 2);
-    //assert_eq!(x.items[0].item, pq! {
-        ///// docstring1
-        //#[bar] fn a_view () {}
-    //});
-    //assert_eq!(x.items[1].item, pq! {
-        //#[baz]
-        ///// docstring2
-        //#[baz] fn is_not_view () {}
-    //});
-    //assert_eq!(x.syms, vec![
-        //ViewArm( { symbol: pq! { ":view1" }, name: pq! { a_view }, },
-    //]);
+    assert_eq!(x.target, expected_target);
+    assert_eq!(x.items.len(), 2);
+    assert_eq!(x.items[0].item, pq! {
+        /// docstring1
+        #[bar] fn a_view () {}
+    });
+    assert_eq!(x.items[1].item, pq! {
+        #[baz]
+        /// docstring2
+        #[baz] fn is_not_view () {}
+    });
+    assert_eq!(x.syms, vec![
+        ViewSym { symbol: pq! { ":view1" }, name: pq! { a_view }, },
+    ]);
 }
 
 #[cfg(test)] #[test] fn test_view_definition () {