Part of the work for a doc handler

schala-codegen/src/lib.rs

@@ -1,5 +1,4 @@
 #![feature(trace_macros)]
-#![feature(proc_macro)]
 extern crate proc_macro;
 #[macro_use]
 extern crate quote;
@@ -52,7 +51,7 @@ fn extract_attribute_list(name: &str, attrs: &Vec<Attribute>) -> Option<Vec<(Ide
   })
 }
 
-#[proc_macro_derive(ProgrammingLanguageInterface, attributes(LanguageName, SourceFileExtension, PipelineSteps))]
+#[proc_macro_derive(ProgrammingLanguageInterface, attributes(LanguageName, SourceFileExtension, PipelineSteps, DocMethod))]
 pub fn derive_programming_language_interface(input: TokenStream) -> TokenStream {
   let ast: DeriveInput = syn::parse(input).unwrap();
   let name = &ast.ident;
@@ -62,6 +61,7 @@ pub fn derive_programming_language_interface(input: TokenStream) -> TokenStream
   let file_ext = extract_attribute_arg_by_name("SourceFileExtension", attrs).expect("SourceFileExtension is required");
   let passes = extract_attribute_list("PipelineSteps", attrs).expect("PipelineSteps are required");
   let pass_idents = passes.iter().map(|x| x.0);
+  let doc_method: Option<String> = extract_attribute_arg_by_name("DocMethod", attrs);
 
   //let pass_names: Vec<String> = passes.iter().map(|pass| pass.0.to_string()).collect();
   let pass_descriptors = passes.iter().map(|pass| {
@@ -97,6 +97,8 @@ pub fn derive_programming_language_interface(input: TokenStream) -> TokenStream
         //vec![ #(PassDescriptor { name: #pass_names.to_string(), debug_options: vec![] }),* ]
       }
     }
+    //TODO if  doc_method is defined, add code here
   };
+
   tokens.into()
 }

schala-lang/src/lib.rs

@@ -35,12 +35,18 @@ mod eval;
 #[LanguageName = "Schala"]
 #[SourceFileExtension = "schala"]
 #[PipelineSteps(tokenizing, parsing(compact,expanded,trace), symbol_table, typechecking, ast_reducing, eval)]
+#[DocMethod = "get_doc"]
 pub struct Schala {
   state: eval::State<'static>,
   symbol_table: Rc<RefCell<symbol_table::SymbolTable>>,
   type_context: typechecking::TypeContext<'static>,
 }
 
+impl Schala {
+  fn get_doc(&self, _commands: &Vec<&str>) -> Option<String> {
+    Some(format!("yup this is getting called right"))
+  }
+}
 
 impl Schala {
   fn new_blank_env() -> Schala {

schala-repl/src/language.rs

@@ -156,7 +156,7 @@ pub trait ProgrammingLanguageInterface {
   fn custom_interpreter_directives_help(&self) -> String {
     format!(">> No custom interpreter directives specified <<")
   }
-  fn get_doc(&mut self, _commands: &Vec<&str>) -> Option<String> {
+  fn get_doc(&self, _commands: &Vec<&str>) -> Option<String> {
     None
   }
 }