add struct example

collects/tests/honu/struct-patterns.honu

@@ -0,0 +1,5 @@
+#lang honu
+
+provide structField;
+
+pattern structField (name_result) [name:identifier];

collects/tests/honu/struct-use.honu

@@ -0,0 +1,12 @@
+#lang honu
+
+require "struct.honu";
+
+struct foo {a b c};
+
+z = foo(1, 2, 3);
+y = 3;
+y = 9;
+// x = foo(1, 2, 3);
+
+display(z.a);

collects/tests/honu/struct.honu

@@ -0,0 +1,10 @@
+#lang honu
+
+require (forSyntax "struct-patterns.honu");
+
+provide struct;
+macro struct () {
+  _ name {field:structField ...} ;
+} {
+  schemeSyntax#sx(honu-struct name (field_name_result ...))
+}