Reject #[ds(...)] attribute for lattices

Author: s-arash

ascent_macro/src/ascent_codegen.rs

@@ -257,7 +257,8 @@ pub(crate) fn compile_mir(mir: &AscentMir, is_ascent_run: bool) -> proc_macro2::
 
    let mut rel_codegens = vec![];
    for rel in mir.relations_ir_relations.keys() {
-      let macro_path = &mir.relations_metadata[rel].ds_macro_path;
+      let Some(ds_attr) = &mir.relations_metadata[rel].ds_attr else { continue };
+      let macro_path = &ds_attr.path;
       let macro_input = rel_ds_macro_input(rel, mir);
       rel_codegens.push(quote_spanned! { macro_path.span()=> #macro_path::rel_codegen!{#macro_input} });
    }
@@ -341,12 +342,16 @@ pub(crate) fn compile_mir(mir: &AscentMir, is_ascent_run: bool) -> proc_macro2::
 }
 
 fn rel_ind_common_type(rel: &RelationIdentity, mir: &AscentMir) -> Type {
-   if rel.is_lattice {
-      parse_quote! { () }
-   } else {
-      let macro_path = &mir.relations_metadata[rel].ds_macro_path;
-      let macro_input = rel_ds_macro_input(rel, mir);
-      parse_quote_spanned! { macro_path.span()=> #macro_path::rel_ind_common!(#macro_input) }
+   match &mir.relations_metadata[rel].ds_attr {
+      None => {
+         assert!(rel.is_lattice);
+         parse_quote! { () }
+      },
+      Some(ds_attr) => {
+         let macro_path = &ds_attr.path;
+         let macro_input = rel_ds_macro_input(rel, mir);
+         parse_quote_spanned! { macro_path.span()=> #macro_path::rel_ind_common!(#macro_input) }
+      },
    }
 }
 
@@ -376,7 +381,7 @@ fn rel_index_type(rel: &IrRelation, mir: &AscentMir) -> Type {
       };
       syn::parse2(res).unwrap()
    } else {
-      let macro_path = &mir.relations_metadata[&rel.relation].ds_macro_path;
+      let macro_path = &mir.relations_metadata[&rel.relation].ds_attr.as_ref().unwrap().path;
       let span = macro_path.span();
       let macro_input = rel_ds_macro_input(&rel.relation, mir);
       if rel.is_full_index() {
@@ -391,16 +396,20 @@ fn rel_index_type(rel: &IrRelation, mir: &AscentMir) -> Type {
 fn rel_type(rel: &RelationIdentity, mir: &AscentMir) -> Type {
    let field_types = tuple_type(&rel.field_types);
 
-   if rel.is_lattice {
-      if mir.is_parallel {
-         parse_quote! {::ascent::boxcar::Vec<::std::sync::RwLock<#field_types>>}
-      } else {
-         parse_quote! {::std::vec::Vec<#field_types>}
-      }
-   } else {
-      let macro_path = &mir.relations_metadata[rel].ds_macro_path;
-      let macro_input = rel_ds_macro_input(rel, mir);
-      parse_quote_spanned! {macro_path.span()=> #macro_path::rel!(#macro_input) }
+   match &mir.relations_metadata[rel].ds_attr {
+      None => {
+         assert!(rel.is_lattice);
+         if mir.is_parallel {
+            parse_quote! {::ascent::boxcar::Vec<::std::sync::RwLock<#field_types>>}
+         } else {
+            parse_quote! {::std::vec::Vec<#field_types>}
+         }
+      },
+      Some(ds_attr) => {
+         let macro_path = &ds_attr.path;
+         let macro_input = rel_ds_macro_input(rel, mir);
+         parse_quote_spanned! {macro_path.span()=> #macro_path::rel!(#macro_input) }
+      },
    }
 }
 
@@ -416,7 +425,7 @@ fn rel_ds_macro_input(rel: &RelationIdentity, mir: &AscentMir) -> TokenStream {
       .iter()
       .sorted_by_key(|r| &r.indices)
       .map(|ir_rel| rel_index_to_macro_input(&ir_rel.indices));
-   let args = &mir.relations_metadata[rel].ds_macro_args;
+   let args = &mir.relations_metadata[rel].ds_attr.as_ref().expect("must have the ds attribute").args;
    let par: Ident = if mir.is_parallel {
       parse_quote_spanned! {span=> par}
    } else {

ascent_macro/src/ascent_hir.rs

@@ -5,7 +5,7 @@ use std::rc::Rc;
 use itertools::Itertools;
 use proc_macro2::{Ident, Span, TokenStream};
 use syn::spanned::Spanned;
-use syn::{Attribute, Error, Expr, Pat, Path, Type, parse_quote, parse2};
+use syn::{Attribute, Error, Expr, Pat, Type, parse_quote, parse2};
 
 use crate::AscentProgram;
 use crate::ascent_syntax::{
@@ -95,8 +95,8 @@ pub(crate) struct AscentIr {
 pub(crate) struct RelationMetadata {
    pub initialization: Option<Rc<Expr>>,
    pub attributes: Rc<Vec<Attribute>>,
-   pub ds_macro_path: Path,
-   pub ds_macro_args: TokenStream,
+   /// Will be `Some()` iff the relation is not a lattice
+   pub ds_attr: Option<DsAttributeContents>,
 }
 
 pub(crate) struct IrRule {
@@ -252,7 +252,15 @@ pub(crate) fn compile_ascent_program_to_hir(prog: &AscentProgram, is_parallel: b
       if let Some(init_expr) = &rel.initialization {
          relations_initializations.insert(rel_identity.clone(), Rc::new(init_expr.clone()));
       }
-      let ds_attribute = get_ds_attr(&rel.attrs)?.unwrap_or_else(|| config.default_ds.clone());
+      let ds_attribute = get_ds_attr(&rel.attrs)?;
+
+      let ds_attribute = match (ds_attribute, rel.is_lattice) {
+         (None, true) => None,
+         (None, false) => Some(config.default_ds.clone()),
+         (Some(attr), true) =>
+            return Err(Error::new(attr.path.span(), "`lattice`s cannot have custom data structure providers")),
+         (Some(attr), false) => Some(attr),
+      };
 
       relations_metadata.insert(rel_identity.clone(), RelationMetadata {
          initialization: rel.initialization.clone().map(Rc::new),
@@ -265,8 +273,7 @@ pub(crate) fn compile_ascent_program_to_hir(prog: &AscentProgram, is_parallel: b
                .cloned()
                .collect_vec(),
          ),
-         ds_macro_path: ds_attribute.path,
-         ds_macro_args: ds_attribute.args,
+         ds_attr: ds_attribute,
       });
       // relations_no_indices.insert(rel_identity, rel_no_index);
    }