Adds sigilless slurpy, closes #2675

Author: JJ

doc/Type/Signature.pod6

@@ -637,6 +637,17 @@ each argument to those Scalars.  If the original argument also had an
 intermediary Scalar it is bypassed during this process, and is not available
 inside the called function.
 
+Sigilled parameters will always impose a context on the collected arguments.
+Sigilless parameters can also be used slurpily, preceded by a + sign, to
+work with whatever initial type they started with:
+
+=for code
+sub zipi( +zape ) {
+    zape.^name => zape
+};
+say zipi( "Hey "); # OUTPUT: «List => (Hey )␤»
+say zipi( 1...* ); # OUTPUT: «Seq => (...)␤»
+
 Slurpy parameters have special behaviors when combined with some
 L<traits and modifiers|#Parameter_Traits_and_Modifiers>,
 as described in