Merge pull request #8209 from dotty-staging/add-tests-to-scoped-quoted-expr

Add tests to scoped quoted Expr prototype

Author: liufengyun

tests/neg/scoped-quoted-expr-proto.scala

@@ -81,3 +81,61 @@ package b {
   }
 
 }
+
+package c {
+
+  trait QCtx { qctx =>
+    type Expr[+T]
+    type Type[T]
+    type NestedSCtx = SCtx {
+      type NestedQCtx = QCtx { type Expr[+T] >: qctx.Expr[T]; type Type[T] >: qctx.Type[T] }
+    }
+  }
+
+  trait SCtx {
+    type NestedQCtx <: QCtx
+  }
+
+  /*Quote*/ def q[T](using qctx: QCtx)(x: qctx.NestedSCtx ?=> T): qctx.Expr[T] = ???
+  /*Splice*/ def s[T](using sctx: SCtx)(x: (qctx: sctx.NestedQCtx) ?=> qctx.Expr[T]): T = ???
+  /*run*/ def r[T](x: (qctx: QCtx) ?=> qctx.Expr[T]): T = ???
+
+  val test: Any = {
+
+    def pow(using qctx: QCtx)(x: qctx.Expr[Double], n: Int): qctx.Expr[Double] =
+      if n == 0 then q{1.0} else q{ s{x} * s{pow(x, n - 1)} }
+
+    r {
+      q{ (x: Double) => s{pow(q{x}, 5)} }
+    }
+
+    r {
+      q{ (x: Double) =>
+        s{
+          val y = q{x}
+          pow(q{s{y}}, 5)
+        }
+      }
+    }
+
+    r {
+      val a = q{ 4.0 }
+      q{ (x: Double) =>
+        s{
+          pow(q{s{a}}, 5)
+        }
+      }
+    }
+
+    r { qctx ?=>
+      var escaped: qctx.Expr[Double] = ???
+      q{ (x: Double) =>
+        s{
+          escaped = q{x} // error
+          pow(q{x}, 5)
+        }
+      }
+    }
+  }
+
+}