add Ppostln

can post values from inside a pattern

wslib-classes/Main Features/Patterns/Ppostln.sc

@@ -0,0 +1,21 @@
+Ppostln : Pattern {
+	var <>pattern, <>prefix;
+	*new { |pattern, prefix|
+		^super.newCopyArgs(pattern, prefix)
+	}
+	storeArgs { ^[pattern] }
+	embedInStream { arg inval;
+		var outval;
+		var stream = pattern.asStream;
+		loop {
+			prefix !? _.post;
+			outval = stream.next(inval).postln;
+			inval = outval.yield;
+		};
+	}
+}
+
++ Pattern {
+	ppostln { ^Ppostln( this ) }
+	poll { |prefix| ^Ppostln( this, prefix ) }
+}