fixing inconststent context for function

hblang/README.md

@@ -631,6 +631,7 @@ min := fn(a: int, b: int): int {
 ```hb
 Point := struct {x: int, y: int}
 Buffer := struct {}
+Transform := Point
 ColorBGRA := Point
 
 line := fn(buffer: Buffer, p0: Point, p1: Point, color: ColorBGRA, thickness: int): void {
@@ -658,8 +659,35 @@ line_high := fn(buffer: Buffer, p0: Point, p1: Point, color: ColorBGRA): void {
 	return
 }
 
-main := fn(): int {
+screenidx := @use("screen.hb").screenidx
-	line(.(), .(0, 0), .(0, 0), .(0, 0), 10)
+
+rect_line := fn(buffer: Buffer, pos: Point, tr: Transform, color: ColorBGRA, thickness: int): void {
+	t := 0
+	y := 0
+	x := 0
+	loop if t == thickness break else {
+		y = pos.y
+		x = pos.x
+		loop if y == pos.y + tr.x break else {
+			a := 1 + @inline(screenidx, 10)
+			a = 1 + @inline(screenidx, 2)
+			y += 1
+		}
+		t += 1
+	}
 	return
 }
+
+main := fn(): int {
+	line(.(), .(0, 0), .(0, 0), .(0, 0), 10)
+	rect_line(.(), .(0, 0), .(0, 0), .(0, 0), 10)
+	return
+}
+
+// in module: screen.hb
+
+screenidx := fn(orange: int): int {
+	return orange
+}
+
 ```

hblang/src/codegen.rs

@@ -1538,8 +1538,12 @@ impl Codegen {
 
                 let loc = self.alloc_ret(sig.ret, ctx, true);
                 let prev_ret_reg = std::mem::replace(&mut self.ci.inline_ret_loc, loc);
+                let prev_file = std::mem::replace(&mut self.ci.file, fuc.file);
+                let prev_ret = std::mem::replace(&mut self.ci.ret, Some(sig.ret));
                 self.expr(body);
                 let loc = std::mem::replace(&mut self.ci.inline_ret_loc, prev_ret_reg);
+                self.ci.file = prev_file;
+                self.ci.ret = prev_ret;
 
                 if let Some(last_ret) = self.ci.ret_relocs.last()
                     && last_ret.offset as usize + self.ci.snap.code == self.output.code.len() - 5