Rename define_components! to cgp_preset! with slight improvement (#41)

* Implement for_each_replace macro logic

* Test and export for_each_replace

* Make exclude list optional

* Use for_each_replace inside define_components

* Rename define_compoents to cgp_preset

* Fix body expansion inside substitution

* Reorganize preset constructs

* Reorganize preset AST

* Split out tests for delegate_components

* Try to capture generic parameters in preset

* Remove phantom type inside IsPreset

* Do not include preset generics inside IsPreset impl for now

* Allow generics inside for_each_replace

* Pass replacements as TokenStream

* Add list-based replacement proc macro

* Use replace_with! instead of for_each_replace!

* Use `impl<T> IsPreset<Name> for T` for bulk delegation

* Add changelog

Author: soareschen

CHANGELOG.md

@@ -2,6 +2,14 @@
 
 ## Pre-Release
 
+- Rename `define_components!` to `cgp_preset!` with slight improvement - [#41](https://github.com/contextgeneric/cgp/pull/41)
+    - Introduce `replace_with!` macro that allows replacement of an identifier with a list of component types in the body.
+    - Introduce `for_each_replace!` macro that allows repeated replacement of an identifier with each element of components in the list in the body.
+    - Rename `define_components!` to `cgp_preset!`.
+    - Use `replace_with!` inside the generated `with_preset!` macro.
+    - Re-introduce the `IsPreset` trait to allow bulk delegation of components.
+
+
 - Redesign `derive_component` to `cgp_component` with improved syntax - [#38](https://github.com/contextgeneric/cgp/pull/38)
     - Rename the attribute `#[derive_component]` to `#[cgp_component]`
     - The macro syntax has been changed as follows:

crates/cgp-component-macro-lib/Cargo.toml

@@ -12,7 +12,7 @@ description  = """
 """
 
 [dependencies]
-syn = { version = "2.0.37", features = [ "full" ] }
+syn = { version = "2.0.37", features = [ "full", "extra-traits" ] }
 quote = "1.0.33"
 proc-macro2 = "1.0.67"
 itertools = "0.11.0"

crates/cgp-component-macro-lib/src/delegate_components/ast.rs

@@ -5,20 +5,14 @@ use quote::ToTokens;
 use syn::parse::{Parse, ParseStream};
 use syn::punctuated::Punctuated;
 use syn::token::{Bracket, Colon, Comma, Lt};
-use syn::{braced, bracketed, Generics, Ident, Token, Type};
+use syn::{braced, bracketed, Generics, Token, Type};
 
 pub struct DelegateComponentsAst {
     pub target_type: Type,
     pub target_generics: Generics,
     pub delegate_entries: DelegateEntriesAst,
 }
 
-pub struct DefineComponentsAst {
-    pub components_ident: Ident,
-    pub components_generics: Generics,
-    pub delegate_entries: DelegateEntriesAst,
-}
-
 pub struct DelegateEntriesAst {
     pub entries: Punctuated<DelegateEntryAst, Comma>,
 }
@@ -63,26 +57,6 @@ impl Parse for DelegateComponentsAst {
     }
 }
 
-impl Parse for DefineComponentsAst {
-    fn parse(input: ParseStream) -> syn::Result<Self> {
-        let components_ident: Ident = input.parse()?;
-
-        let components_generics = if input.peek(Lt) {
-            input.parse()?
-        } else {
-            Default::default()
-        };
-
-        let delegate_entries: DelegateEntriesAst = input.parse()?;
-
-        Ok(Self {
-            components_ident,
-            components_generics,
-            delegate_entries,
-        })
-    }
-}
-
 impl Parse for DelegateEntriesAst {
     fn parse(input: ParseStream) -> syn::Result<Self> {
         let entries = {

crates/cgp-component-macro-lib/src/delegate_components/define.rs

@@ -4,8 +4,8 @@ use quote::ToTokens;
 use crate::delegate_components::ast::DelegateComponentsAst;
 use crate::delegate_components::impl_delegate::impl_delegate_components;
 
-pub fn delegate_components(body: TokenStream) -> TokenStream {
-    let ast: DelegateComponentsAst = syn::parse2(body).unwrap();
+pub fn delegate_components(body: TokenStream) -> syn::Result<TokenStream> {
+    let ast: DelegateComponentsAst = syn::parse2(body)?;
 
     let impl_items = impl_delegate_components(
         &ast.target_type,
@@ -19,5 +19,5 @@ pub fn delegate_components(body: TokenStream) -> TokenStream {
         output.extend(impl_item.to_token_stream());
     }
 
-    output
+    Ok(output)
 }

crates/cgp-component-macro-lib/src/delegate_components/delegate.rs

@@ -1,11 +1,8 @@
 pub mod ast;
-pub mod define;
 pub mod define_struct;
 pub mod delegate;
 pub mod delegates_to;
 pub mod impl_delegate;
 pub mod merge_generics;
-pub mod substitution_macro;
 
-pub use define::define_components;
 pub use delegate::delegate_components;