doc unspace

doc/Language/syntax.pod6

@@ -56,6 +56,19 @@ if True {say "Hello"}
 
 though you can't leave out any of the remaining whitespace.
 
+=head2 Unspace
+
+In many places where the compiler would not allow a space you can use any
+whitespace that is quoted with a backslash. Unspaces in tokens are not
+supported. Newlines that are unspaced still count when the compiler produces
+line numbers. Usecases for unspace are separation of postfix operators and
+routine argument lists.
+
+    sub alignment(+@l) { +@l };$
+    sub long-name-alignment(+@l) { +@l };$
+    alignment\         (1,2,3,4)>>.say;$
+    long-name-alignment(3,5)\   >>.say;$
+
 =head2 Separating Statements
 
 A Perl 6 program is a list of statements, separated by semicolons C<;>.