--- a/progs/lexer/lexer.sc	Tue Oct 27 13:46:01 2020 +0000
+++ b/progs/lexer/lexer.sc	Tue Oct 27 13:51:34 2020 +0000
@@ -6,6 +6,7 @@
 //   amm lexer.sc small
 //   amm lexer.sc fib
 //   amm lexer.sc loops
+//   amm lexer.sc email
 //
 //   amm lexer.sc all
 
@@ -298,27 +299,30 @@
   println(escape(lexing_simp(WHILE_REGS, prog3)).mkString("\n"))
 }
 
+@doc("Email Test")
+@main
+def email() = {
+  val lower = "abcdefghijklmnopqrstuvwxyz"
 
+  val NAME = RECD("name", PLUS(RANGE(lower ++ "_.-")))
+  val DOMAIN = RECD("domain", PLUS(RANGE(lower ++ "-")))
+  val RE = RANGE(lower ++ ".")
+  val TOPLEVEL = RECD("top", (RE ~ RE) |
+                             (RE ~ RE ~ RE) | 
+                             (RE ~ RE ~ RE ~ RE) | 
+                             (RE ~ RE ~ RE ~ RE ~ RE) |
+                             (RE ~ RE ~ RE ~ RE ~ RE ~ RE))
+
+  val EMAIL = NAME ~ "@" ~ DOMAIN ~ "." ~ TOPLEVEL
+
+  println(lexing_simp(EMAIL, "christian.urban@kcl.ac.uk"))
+}
 
 
 @doc("All tests.")
 @main
-def all() = { small(); fib() ; loops() } 
+def all() = { small(); fib() ; loops() ; email() } 
 
 
-val SYM1 = RANGE("ABCDEFGHIJKLMNOPQRSTUVXYZabcdefghijklmnopqrstuvwxyz_.-")
-val NAME = RECD("name", PLUS(SYM1))
-
-val SYM2 = RANGE("ABCDEFGHIJKLMNOPQRSTUVXYZabcdefghijklmnopqrstuvwxyz-")
-val DOMAIN = RECD("domain", PLUS(SYM2))
 
-val RE = RANGE("ABCDEFGHIJKLMNOPQRSTUVXYZabcdefghijklmnopqrstuvwxyz.")
-val TOPLEVEL = RECD("tl", (RE ~ RE) |
-                          (RE ~ RE ~ RE) | 
-                          (RE ~ RE ~ RE ~ RE) | 
-                          (RE ~ RE ~ RE ~ RE ~ RE) |
-                          (RE ~ RE ~ RE ~ RE ~ RE ~ RE))
 
-val EMAIL = NAME ~ "@" ~ DOMAIN ~ "." ~ TOPLEVEL
-
-println(lexing_simp(EMAIL, "christian.urban@kcl.ac.uk"))