X::Signature::Placeholder

lib/X/Signature/Placeholder.pod

@@ -0,0 +1,28 @@
+=begin pod
+
+=TITLE class X::Signature::Placeholder
+
+    class X::Signature::Placeholder does X::Comp
+
+Compile time error thrown when a block has both an explicit signature
+and placeholder parameters.
+
+For example
+
+    sub f() { $^x }
+
+dies with
+
+    ===SORRY!===
+    Placeholder variable '$^x' cannot override existing signature
+
+=head1 Methods
+
+=head2 placeholder
+
+    method placeholder() returns Str:D
+
+Returns the name of a placeholder that was used in a block that already
+had a signature.
+
+=end pod