....

examples/issue-0003.sx

@@ -0,0 +1,25 @@
+// Issue: enum literal inference in match expression used as assignment RHS
+// When a match expression is assigned to a field with a known enum type,
+// the enum literals in case arms should infer their type from the assignment target.
+
+Color :: enum {
+    red;
+    green;
+    blue;
+    none;
+}
+
+Thing :: struct {
+    color: Color;
+}
+
+main :: () {
+    t : Thing = ---;
+    value : u8 = 1;
+    t.color = if value == {
+        case 1: .red;      // error: cannot infer enum type for literal
+        case 2: .green;
+        case 3: .blue;
+        else: .none;
+    };
+}

examples/issue-0004-defs.sx

@@ -0,0 +1,18 @@
+#import "modules/std.sx";
+
+Color :: struct {
+    r, g, b, a: u8;
+}
+
+COLOR_WHITE :: Color.{ r = 255, g = 255, b = 255, a = 255 };
+
+// Additional case: struct constant with enum-typed fields
+HAlign :: enum { leading; center; trailing; }
+VAlign :: enum { top; center; bottom; }
+
+Alignment :: struct {
+    h: HAlign;
+    v: VAlign;
+}
+
+ALIGN_CENTER :: Alignment.{ h = .center, v = .center };

examples/issue-0004.sx

@@ -0,0 +1,20 @@
+// Issue: top-level constants from imported files are not visible
+// COLOR_WHITE works after fix, but ALIGN_CENTER (struct with enum fields) does not.
+// Error: undefined identifier 'ALIGN_CENTER'
+
+#import "modules/std.sx";
+#import "examples/issue-0004-defs.sx";
+
+Thing :: struct {
+    color: Color;
+    alignment: Alignment;
+
+    make :: () -> Thing {
+        Thing.{ color = COLOR_WHITE, alignment = ALIGN_CENTER };
+    }
+}
+
+main :: () {
+    t := Thing.make();
+    print("{}\n", t.color.r);
+}

src/codegen.zig

@@ -2694,6 +2694,17 @@ pub const CodeGen = struct {
             .struct_literal => |sl| {
                 return self.evalConstantStruct(sl, target_ty);
             },
+            .enum_literal => |el| {
+                if (target_ty.isEnum()) {
+                    const variants = self.lookupEnumVariants(target_ty.enum_type) orelse return null;
+                    for (variants, 0..) |vname, i| {
+                        if (std.mem.eql(u8, vname, el.name)) {
+                            return c.LLVMConstInt(llvm_ty, @intCast(i), 0);
+                        }
+                    }
+                }
+                return null;
+            },
             else => return null,
         }
     }
@@ -2730,8 +2741,10 @@ pub const CodeGen = struct {
 
     /// Register a top-level value constant (e.g., `SPECIAL_VALUE :u8: 42;`) as an LLVM global.
     fn registerTopLevelConstant(self: *CodeGen, cd: ast.ConstDecl) !void {
-        const ta = cd.type_annotation orelse return; // need explicit type for top-level constants
-        const sx_ty = self.resolveType(ta);
+        const sx_ty = if (cd.type_annotation) |ta|
+            self.resolveType(ta)
+        else
+            self.inferType(cd.value);
         if (sx_ty == .void_type) return;
 
         const const_val = self.evalConstant(cd.value, sx_ty) orelse return;
@@ -6106,6 +6119,18 @@ pub const CodeGen = struct {
             return self.wrapOptional(val, target_ty);
         }
 
+        // Match/if expression with enum/union target: propagate type context into arms
+        // so enum literals like .red can resolve their type from the assignment target
+        if ((node.data == .match_expr or node.data == .if_expr) and
+            (target_ty.isEnum() or target_ty.isUnion()))
+        {
+            const saved = self.current_return_type;
+            self.current_return_type = target_ty;
+            const val = try self.genExpr(node);
+            self.current_return_type = saved;
+            return val;
+        }
+
         // Enum literal assigned to enum type: resolve variant value
         if (node.data == .enum_literal and target_ty.isEnum()) {
             return self.genEnumLiteral(node.data.enum_literal.name, target_ty.enum_type);