parse a shortname prefix before Effects

compiler/load/src/file.rs

@@ -648,6 +648,7 @@ enum Msg<'a> {
         module_docs: Option<ModuleDocumentation>,
     },
     MadeEffectModule {
+        type_shortname: &'a str,
         constrained_module: ConstrainedModule,
         canonicalization_problems: Vec<roc_problem::can::Problem>,
         module_docs: ModuleDocumentation,
@@ -1569,6 +1570,7 @@ fn update<'a>(
             constrained_module,
             canonicalization_problems,
             module_docs,
+            type_shortname: _,
         } => {
             let module_id = constrained_module.module.module_id;
 
@@ -3141,6 +3143,7 @@ fn fabricate_effects_module<'a>(
     Ok((
         module_id,
         Msg::MadeEffectModule {
+            type_shortname: effects.type_shortname,
             constrained_module,
             canonicalization_problems: module_output.problems,
             module_docs,

compiler/parse/src/header.rs

@@ -143,11 +143,13 @@ pub struct PlatformHeader<'a> {
     pub after_provides: &'a [CommentOrNewline<'a>],
 }
 
+/// e.g. fx.Effects
 #[derive(Clone, Debug, PartialEq)]
 pub struct Effects<'a> {
     pub spaces_before_effects_keyword: &'a [CommentOrNewline<'a>],
     pub spaces_after_effects_keyword: &'a [CommentOrNewline<'a>],
     pub spaces_after_type_name: &'a [CommentOrNewline<'a>],
+    pub type_shortname: &'a str,
     pub type_name: &'a str,
     pub entries: Vec<'a, Loc<TypedIdent<'a>>>,
 }

compiler/parse/src/module.rs

@@ -490,6 +490,11 @@ fn effects<'a>() -> impl Parser<'a, Effects<'a>> {
         let (spaces_before_effects_keyword, state) =
             skip_second!(space1(0), ascii_string("effects")).parse(arena, state)?;
         let (spaces_after_effects_keyword, state) = space1(0).parse(arena, state)?;
+
+        // e.g. `fx.`
+        let (type_shortname, state) =
+            skip_second!(lowercase_ident(), ascii_char(b'.')).parse(arena, state)?;
+
         let ((type_name, spaces_after_type_name), state) =
             and!(uppercase_ident(), space1(0)).parse(arena, state)?;
         let (entries, state) = collection!(
@@ -506,6 +511,7 @@ fn effects<'a>() -> impl Parser<'a, Effects<'a>> {
                 spaces_before_effects_keyword,
                 spaces_after_effects_keyword,
                 spaces_after_type_name,
+                type_shortname,
                 type_name,
                 entries,
             },

examples/benchmarks/platform/Pkg-Config.roc

@@ -4,7 +4,7 @@ platform folkertdev/foo
     packages {}
     imports [ Task ]
     provides [ mainForHost ]
-    effects Effect
+    effects fx.Effect
         {
             putLine : Str -> Effect {},
             getInt : Effect { value: I64, errorCode: [ A, B ], isError: Bool }