Add ranges to EBNF syntax

This works:
  <EBNF letter = [a-zA-Z] EBNF>
and
  <EBNF not-digit = [^0-9] EBNF>

extra/peg/ebnf/ebnf-tests.factor

@@ -119,3 +119,27 @@ IN: peg.ebnf.tests
 { V{ 1 2 } } [
   "foo=('a') [[ drop 1 ]] ('b') [[ drop 2 ]]" ebnf>quot with-compilation-unit "ab" foo parse parse-result-ast 
 ] unit-test
+
+{ CHAR: A } [
+  "foo=[A-Z]" ebnf>quot with-compilation-unit "A" foo parse parse-result-ast 
+] unit-test
+
+{ CHAR: Z } [
+  "foo=[A-Z]" ebnf>quot with-compilation-unit "Z" foo parse parse-result-ast 
+] unit-test
+
+{ f } [
+  "foo=[A-Z]" ebnf>quot with-compilation-unit "0" foo parse  
+] unit-test
+
+{ CHAR: 0 } [
+  "foo=[^A-Z]" ebnf>quot with-compilation-unit "0" foo parse parse-result-ast 
+] unit-test
+
+{ f } [
+  "foo=[^A-Z]" ebnf>quot with-compilation-unit "A" foo parse  
+] unit-test
+
+{ f } [
+  "foo=[^A-Z]" ebnf>quot with-compilation-unit "Z" foo parse  
+] unit-test

extra/peg/ebnf/ebnf.factor

@@ -9,6 +9,7 @@ IN: peg.ebnf
 TUPLE: ebnf-non-terminal symbol ;
 TUPLE: ebnf-terminal symbol ;
 TUPLE: ebnf-any-character ;
+TUPLE: ebnf-range pattern ;
 TUPLE: ebnf-ensure-not group ;
 TUPLE: ebnf-choice options ;
 TUPLE: ebnf-sequence elements ;
@@ -22,6 +23,7 @@ TUPLE: ebnf rules ;
 C: <ebnf-non-terminal> ebnf-non-terminal
 C: <ebnf-terminal> ebnf-terminal
 C: <ebnf-any-character> ebnf-any-character
+C: <ebnf-range> ebnf-range
 C: <ebnf-ensure-not> ebnf-ensure-not
 C: <ebnf-choice> ebnf-choice
 C: <ebnf-sequence> ebnf-sequence
@@ -69,6 +71,9 @@ M: ebnf-non-terminal (generate-parser) ( ast -- id )
 M: ebnf-any-character (generate-parser) ( ast -- id )
   drop [ drop t ] satisfy store-parser ;
 
+M: ebnf-range (generate-parser) ( ast -- id )
+  ebnf-range-pattern range-pattern store-parser ;
+
 M: ebnf-choice (generate-parser) ( ast -- id )
   ebnf-choice-options [
     generate-parser get-parser 
@@ -164,6 +169,14 @@ DEFER: 'rhs'
   #! A parser to match the symbol for any character match.
   [ CHAR: . = ] satisfy [ drop <ebnf-any-character> ] action ;
 
+: 'range-parser' ( -- parser )
+  #! Match the syntax for declaring character ranges
+  [
+    "[" syntax ,
+    [ CHAR: ] = not ] satisfy repeat1 , 
+    "]" syntax ,
+  ] seq* [ first >string <ebnf-range> ] action ;
+ 
 : 'element' ( -- parser )
   #! An element of a rule. It can be a terminal or a 
   #! non-terminal but must not be followed by a "=". 
@@ -173,6 +186,7 @@ DEFER: 'rhs'
     [ 
       'non-terminal' ,
       'terminal' ,
+      'range-parser' ,
       'any-character' ,
     ] choice* ,
     "=" syntax ensure-not ,