Properly scope parameters inside of anonymous functions

myst.sublime-syntax

@@ -84,18 +84,7 @@ contexts:
         1: keyword.control.function.myst
         2: entity.name.function.public.myst
         4: punctuation.definition.parameters.begin.myst
-      push:
-        - include: parameter
-        - meta_scope: meta.function.body.myst
-        - match: ;
-          pop: true
-        - match: $
-          pop: true
-        - match: ','
-          scope: punctuation.separator.parameter.myst
-        - match: \)$
-          scope: punctuation.definition.parameters.end.myst
-          pop: true
+      push: function_parameters
     - match: \bfn\b
       scope: keyword.control.anonymous.myst
       push: anonymous_function
@@ -159,6 +148,19 @@ contexts:
       pop: true
     - include: parameter
 
+  function_parameters:
+    - include: parameter
+    - meta_scope: meta.function.body.myst
+    - match: ;
+      pop: true
+    - match: $
+      pop: true
+    - match: ','
+      scope: punctuation.separator.parameter.myst
+    - match: \)$
+      scope: punctuation.definition.parameters.end.myst
+      pop: true
+
   comments:
     - match: \#.*
       scope: comment.line.number-sign
@@ -243,4 +245,6 @@ contexts:
     - match: -\>
       # TODO: This needs a better scope name
       scope: keyword.operator.assignment.stab.myst
+    - match: '\('
+      push: function_parameters
     - include: main

sample.mt

@@ -33,6 +33,20 @@ deftype Person
 
   def foo()
     days100per100 = 100
+
+    func = fn
+      ->(a, *rest, [1, 2, 3] =: _ignored, &block) do
+        a + b
+        raise "no"
+      rescue str : String
+        0
+      rescue
+        nil
+      end
+
+      ->(_other) { nil }
+    end
+
     raise "woops\nit broke"
   rescue msg : String
     while msg.size <= 10_000_000