diff --git a/etc/ebnf.ebnf b/etc/ebnf.ebnf
index 1f8dfce..ad777f2 100644
--- a/etc/ebnf.ebnf
+++ b/etc/ebnf.ebnf
@@ -39,9 +39,9 @@
 
     [13] HEX        ::= '#x' ([a-f] | [A-F] | [0-9])+
 
-    [14] RANGE      ::= '[' ((R_CHAR '-' R_CHAR) | (HEX '-' HEX) | R_CHAR | HEX)+ '-'? ']'
+    [14] RANGE      ::= '[' ('-' ((R_CHAR '-' R_CHAR) | (HEX '-' HEX) | R_CHAR | HEX)+ | ((R_CHAR '-' R_CHAR) | (HEX '-' HEX) | R_CHAR | HEX)+ '-'?) ']'
 
-    [15] O_RANGE    ::= '[^' ((R_CHAR '-' R_CHAR) | (HEX '-' HEX) | R_CHAR | HEX)+ '-'? ']'
+    [15] O_RANGE    ::= '[^' ('-' ((R_CHAR '-' R_CHAR) | (HEX '-' HEX) | R_CHAR | HEX)+ | ((R_CHAR '-' R_CHAR) | (HEX '-' HEX) | R_CHAR | HEX)+ '-'?) ']'
 
     # Strings are unescaped Unicode, excepting control characters and hash (#)
     [16] STRING1    ::= '"' (CHAR - '"')* '"'
diff --git a/etc/ebnf.ll1.sxp b/etc/ebnf.ll1.sxp
index 1912786..80ba750 100644
--- a/etc/ebnf.ll1.sxp
+++ b/etc/ebnf.ll1.sxp
@@ -104,9 +104,15 @@
      (terminal O_SYMBOL "12a" (plus (alt (range "a-z") (range "A-Z") (range "0-9") '_' '.')))
      (terminal HEX "13" (seq '#x' (plus (alt (range "a-f") (range "A-F") (range "0-9")))))
      (terminal RANGE "14"
-      (seq '[' (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)) (opt '-') ']'))
+      (seq '['
+       (alt
+        (seq '-' (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)))
+        (seq (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)) (opt '-'))) ']' ))
      (terminal O_RANGE "15"
-      (seq '[^' (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)) (opt '-') ']'))
+      (seq '[^'
+       (alt
+        (seq '-' (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)))
+        (seq (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)) (opt '-'))) ']' ))
      (terminal STRING1 "16" (seq '"' (star (diff CHAR '"')) '"'))
      (terminal STRING2 "17" (seq "'" (star (diff CHAR "'")) "'"))
      (terminal CHAR "18"
diff --git a/etc/ebnf.peg.rb b/etc/ebnf.peg.rb
index 315e2f6..ea79e21 100644
--- a/etc/ebnf.peg.rb
+++ b/etc/ebnf.peg.rb
@@ -1,4 +1,4 @@
-# This file is automatically generated by ebnf version 2.5.0
+# This file is automatically generated by ebnf version 2.6.0
 # Derived from etc/ebnf.ebnf
 module EBNFMeta
   RULES = [
@@ -38,18 +38,32 @@ module EBNFMeta
     EBNF::Rule.new(:_HEX_3, "13.3", [:range, "a-f"], kind: :terminal).extend(EBNF::PEG::Rule),
     EBNF::Rule.new(:_HEX_4, "13.4", [:range, "A-F"], kind: :terminal).extend(EBNF::PEG::Rule),
     EBNF::Rule.new(:_HEX_5, "13.5", [:range, "0-9"], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:RANGE, "14", [:seq, "[", :_RANGE_1, :_RANGE_2, "]"], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_RANGE_1, "14.1", [:plus, :_RANGE_3], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_RANGE_3, "14.3", [:alt, :_RANGE_4, :_RANGE_5, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_RANGE_4, "14.4", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_RANGE_5, "14.5", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_RANGE_2, "14.2", [:opt, "-"], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:O_RANGE, "15", [:seq, "[^", :_O_RANGE_1, :_O_RANGE_2, "]"], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_O_RANGE_1, "15.1", [:plus, :_O_RANGE_3], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_O_RANGE_3, "15.3", [:alt, :_O_RANGE_4, :_O_RANGE_5, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_O_RANGE_4, "15.4", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_O_RANGE_5, "15.5", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_O_RANGE_2, "15.2", [:opt, "-"], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:RANGE, "14", [:seq, "[", :_RANGE_1, "]"], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_1, "14.1", [:alt, :_RANGE_2, :_RANGE_3], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_2, "14.2", [:seq, "-", :_RANGE_4], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_4, "14.4", [:plus, :_RANGE_5], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_5, "14.5", [:alt, :_RANGE_6, :_RANGE_7, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_6, "14.6", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_7, "14.7", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_3, "14.3", [:seq, :_RANGE_8, :_RANGE_9], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_8, "14.8", [:plus, :_RANGE_10], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_10, "14.10", [:alt, :_RANGE_11, :_RANGE_12, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_11, "14.11", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_12, "14.12", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_9, "14.9", [:opt, "-"], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:O_RANGE, "15", [:seq, "[^", :_O_RANGE_1, "]"], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_1, "15.1", [:alt, :_O_RANGE_2, :_O_RANGE_3], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_2, "15.2", [:seq, "-", :_O_RANGE_4], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_4, "15.4", [:plus, :_O_RANGE_5], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_5, "15.5", [:alt, :_O_RANGE_6, :_O_RANGE_7, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_6, "15.6", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_7, "15.7", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_3, "15.3", [:seq, :_O_RANGE_8, :_O_RANGE_9], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_8, "15.8", [:plus, :_O_RANGE_10], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_10, "15.10", [:alt, :_O_RANGE_11, :_O_RANGE_12, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_11, "15.11", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_12, "15.12", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_9, "15.9", [:opt, "-"], kind: :terminal).extend(EBNF::PEG::Rule),
     EBNF::Rule.new(:STRING1, "16", [:seq, "\"", :_STRING1_1, "\""], kind: :terminal).extend(EBNF::PEG::Rule),
     EBNF::Rule.new(:_STRING1_1, "16.1", [:star, :_STRING1_2], kind: :terminal).extend(EBNF::PEG::Rule),
     EBNF::Rule.new(:_STRING1_2, "16.2", [:diff, :CHAR, "\""], kind: :terminal).extend(EBNF::PEG::Rule),
diff --git a/etc/ebnf.peg.sxp b/etc/ebnf.peg.sxp
index 6125475..408ac5c 100644
--- a/etc/ebnf.peg.sxp
+++ b/etc/ebnf.peg.sxp
@@ -35,18 +35,32 @@
      (terminal _HEX_3 "13.3" (range "a-f"))
      (terminal _HEX_4 "13.4" (range "A-F"))
      (terminal _HEX_5 "13.5" (range "0-9"))
-     (terminal RANGE "14" (seq '[' _RANGE_1 _RANGE_2 ']'))
-     (terminal _RANGE_1 "14.1" (plus _RANGE_3))
-     (terminal _RANGE_3 "14.3" (alt _RANGE_4 _RANGE_5 R_CHAR HEX))
-     (terminal _RANGE_4 "14.4" (seq R_CHAR '-' R_CHAR))
-     (terminal _RANGE_5 "14.5" (seq HEX '-' HEX))
-     (terminal _RANGE_2 "14.2" (opt '-'))
-     (terminal O_RANGE "15" (seq '[^' _O_RANGE_1 _O_RANGE_2 ']'))
-     (terminal _O_RANGE_1 "15.1" (plus _O_RANGE_3))
-     (terminal _O_RANGE_3 "15.3" (alt _O_RANGE_4 _O_RANGE_5 R_CHAR HEX))
-     (terminal _O_RANGE_4 "15.4" (seq R_CHAR '-' R_CHAR))
-     (terminal _O_RANGE_5 "15.5" (seq HEX '-' HEX))
-     (terminal _O_RANGE_2 "15.2" (opt '-'))
+     (terminal RANGE "14" (seq '[' _RANGE_1 ']'))
+     (terminal _RANGE_1 "14.1" (alt _RANGE_2 _RANGE_3))
+     (terminal _RANGE_2 "14.2" (seq '-' _RANGE_4))
+     (terminal _RANGE_4 "14.4" (plus _RANGE_5))
+     (terminal _RANGE_5 "14.5" (alt _RANGE_6 _RANGE_7 R_CHAR HEX))
+     (terminal _RANGE_6 "14.6" (seq R_CHAR '-' R_CHAR))
+     (terminal _RANGE_7 "14.7" (seq HEX '-' HEX))
+     (terminal _RANGE_3 "14.3" (seq _RANGE_8 _RANGE_9))
+     (terminal _RANGE_8 "14.8" (plus _RANGE_10))
+     (terminal _RANGE_10 "14.10" (alt _RANGE_11 _RANGE_12 R_CHAR HEX))
+     (terminal _RANGE_11 "14.11" (seq R_CHAR '-' R_CHAR))
+     (terminal _RANGE_12 "14.12" (seq HEX '-' HEX))
+     (terminal _RANGE_9 "14.9" (opt '-'))
+     (terminal O_RANGE "15" (seq '[^' _O_RANGE_1 ']'))
+     (terminal _O_RANGE_1 "15.1" (alt _O_RANGE_2 _O_RANGE_3))
+     (terminal _O_RANGE_2 "15.2" (seq '-' _O_RANGE_4))
+     (terminal _O_RANGE_4 "15.4" (plus _O_RANGE_5))
+     (terminal _O_RANGE_5 "15.5" (alt _O_RANGE_6 _O_RANGE_7 R_CHAR HEX))
+     (terminal _O_RANGE_6 "15.6" (seq R_CHAR '-' R_CHAR))
+     (terminal _O_RANGE_7 "15.7" (seq HEX '-' HEX))
+     (terminal _O_RANGE_3 "15.3" (seq _O_RANGE_8 _O_RANGE_9))
+     (terminal _O_RANGE_8 "15.8" (plus _O_RANGE_10))
+     (terminal _O_RANGE_10 "15.10" (alt _O_RANGE_11 _O_RANGE_12 R_CHAR HEX))
+     (terminal _O_RANGE_11 "15.11" (seq R_CHAR '-' R_CHAR))
+     (terminal _O_RANGE_12 "15.12" (seq HEX '-' HEX))
+     (terminal _O_RANGE_9 "15.9" (opt '-'))
      (terminal STRING1 "16" (seq '"' _STRING1_1 '"'))
      (terminal _STRING1_1 "16.1" (star _STRING1_2))
      (terminal _STRING1_2 "16.2" (diff CHAR '"'))
diff --git a/etc/ebnf.sxp b/etc/ebnf.sxp
index 435c333..dbd45b0 100644
--- a/etc/ebnf.sxp
+++ b/etc/ebnf.sxp
@@ -16,9 +16,15 @@
      (terminal O_SYMBOL "12a" (plus (alt (range "a-z") (range "A-Z") (range "0-9") '_' '.')))
      (terminal HEX "13" (seq '#x' (plus (alt (range "a-f") (range "A-F") (range "0-9")))))
      (terminal RANGE "14"
-      (seq '[' (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)) (opt '-') ']'))
+      (seq '['
+       (alt
+        (seq '-' (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)))
+        (seq (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)) (opt '-'))) ']' ))
      (terminal O_RANGE "15"
-      (seq '[^' (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)) (opt '-') ']'))
+      (seq '[^'
+       (alt
+        (seq '-' (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)))
+        (seq (plus (alt (seq R_CHAR '-' R_CHAR) (seq HEX '-' HEX) R_CHAR HEX)) (opt '-'))) ']' ))
      (terminal STRING1 "16" (seq '"' (star (diff CHAR '"')) '"'))
      (terminal STRING2 "17" (seq "'" (star (diff CHAR "'")) "'"))
      (terminal CHAR "18"
diff --git a/lib/ebnf/ebnf/meta.rb b/lib/ebnf/ebnf/meta.rb
index c319b09..ea79e21 100644
--- a/lib/ebnf/ebnf/meta.rb
+++ b/lib/ebnf/ebnf/meta.rb
@@ -1,4 +1,4 @@
-# This file is automatically generated by ebnf version 2.5.0
+# This file is automatically generated by ebnf version 2.6.0
 # Derived from etc/ebnf.ebnf
 module EBNFMeta
   RULES = [
@@ -38,19 +38,32 @@ module EBNFMeta
     EBNF::Rule.new(:_HEX_3, "13.3", [:range, "a-f"], kind: :terminal).extend(EBNF::PEG::Rule),
     EBNF::Rule.new(:_HEX_4, "13.4", [:range, "A-F"], kind: :terminal).extend(EBNF::PEG::Rule),
     EBNF::Rule.new(:_HEX_5, "13.5", [:range, "0-9"], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:RANGE, "14", [:seq, "[", :_RANGE_1, :_RANGE_2, :_RANGE_3], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_RANGE_1, "14.1", [:plus, :_RANGE_4], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_RANGE_4, "14.4", [:alt, :_RANGE_5, :_RANGE_6, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_RANGE_5, "14.5", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_RANGE_6, "14.6", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_RANGE_2, "14.2", [:opt, "-"], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_RANGE_3, "14.3", [:diff, "]", :LHS], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:O_RANGE, "15", [:seq, "[^", :_O_RANGE_1, :_O_RANGE_2, "]"], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_O_RANGE_1, "15.1", [:plus, :_O_RANGE_3], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_O_RANGE_3, "15.3", [:alt, :_O_RANGE_4, :_O_RANGE_5, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_O_RANGE_4, "15.4", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_O_RANGE_5, "15.5", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
-    EBNF::Rule.new(:_O_RANGE_2, "15.2", [:opt, "-"], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:RANGE, "14", [:seq, "[", :_RANGE_1, "]"], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_1, "14.1", [:alt, :_RANGE_2, :_RANGE_3], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_2, "14.2", [:seq, "-", :_RANGE_4], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_4, "14.4", [:plus, :_RANGE_5], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_5, "14.5", [:alt, :_RANGE_6, :_RANGE_7, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_6, "14.6", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_7, "14.7", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_3, "14.3", [:seq, :_RANGE_8, :_RANGE_9], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_8, "14.8", [:plus, :_RANGE_10], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_10, "14.10", [:alt, :_RANGE_11, :_RANGE_12, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_11, "14.11", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_12, "14.12", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_RANGE_9, "14.9", [:opt, "-"], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:O_RANGE, "15", [:seq, "[^", :_O_RANGE_1, "]"], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_1, "15.1", [:alt, :_O_RANGE_2, :_O_RANGE_3], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_2, "15.2", [:seq, "-", :_O_RANGE_4], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_4, "15.4", [:plus, :_O_RANGE_5], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_5, "15.5", [:alt, :_O_RANGE_6, :_O_RANGE_7, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_6, "15.6", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_7, "15.7", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_3, "15.3", [:seq, :_O_RANGE_8, :_O_RANGE_9], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_8, "15.8", [:plus, :_O_RANGE_10], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_10, "15.10", [:alt, :_O_RANGE_11, :_O_RANGE_12, :R_CHAR, :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_11, "15.11", [:seq, :R_CHAR, "-", :R_CHAR], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_12, "15.12", [:seq, :HEX, "-", :HEX], kind: :terminal).extend(EBNF::PEG::Rule),
+    EBNF::Rule.new(:_O_RANGE_9, "15.9", [:opt, "-"], kind: :terminal).extend(EBNF::PEG::Rule),
     EBNF::Rule.new(:STRING1, "16", [:seq, "\"", :_STRING1_1, "\""], kind: :terminal).extend(EBNF::PEG::Rule),
     EBNF::Rule.new(:_STRING1_1, "16.1", [:star, :_STRING1_2], kind: :terminal).extend(EBNF::PEG::Rule),
     EBNF::Rule.new(:_STRING1_2, "16.2", [:diff, :CHAR, "\""], kind: :terminal).extend(EBNF::PEG::Rule),
diff --git a/lib/ebnf/terminals.rb b/lib/ebnf/terminals.rb
index 861aa02..33a377b 100644
--- a/lib/ebnf/terminals.rb
+++ b/lib/ebnf/terminals.rb
@@ -1,19 +1,22 @@
 # encoding: utf-8
 # Terminal definitions for the EBNF grammar
 module EBNF::Terminals
-  SYMBOL_BASE  = %r(\b[a-zA-Z0-9_\.]+\b)u.freeze # Word boundaries
-  SYMBOL  = %r((?:#{SYMBOL_BASE}|(?:<#{SYMBOL_BASE}>))(?!\s*::=))u.freeze
-  HEX     = %r(\#x\h+)u.freeze
-  CHAR    = %r([\u0009\u000A\u000D\u0020-\uD7FF\u{10000}-\u{10FFFF}])u.freeze
-  R_CHAR  = %r([\u0009\u000A\u000D\u0020-\u002C\u002E-\u005C\u005E-\uD7FF\u{10000}-\u{10FFFF}])u.freeze
-  LHS     = %r((?:\[#{SYMBOL_BASE}\])?\s*<?#{SYMBOL_BASE}>?\s*::=)u.freeze
-  RANGE   = %r(\[(?:(?:#{R_CHAR}\-#{R_CHAR})|(?:#{HEX}\-#{HEX})|#{R_CHAR}|#{HEX})+-?\])u.freeze
-  RANGE_NOT_LHS = %r(\[(?:(?:#{R_CHAR}\-#{R_CHAR})|(?:#{HEX}\-#{HEX})|#{R_CHAR}|#{HEX})+-?\](?!\s*<?#{SYMBOL_BASE}>?\s*::=))u.freeze
-  O_RANGE = %r(\[\^(?:(?:#{R_CHAR}\-#{R_CHAR})|(?:#{HEX}\-#{HEX}|#{R_CHAR}|#{HEX}))+-?\])u.freeze
-  STRING1 = %r("[\u0009\u000A\u000D\u0020\u0021\u0023-\uD7FF\u{10000}-\u{10FFFF}]*")u.freeze
-  STRING2 = %r('[\u0009\u000A\u000D\u0020-\u0026\u0028-\uD7FF\u{10000}-\u{10FFFF}]*')u.freeze
-  POSTFIX = %r([?*+])u.freeze
-  PASS    = %r((
+  SYMBOL_BASE   = %r(\b[a-zA-Z0-9_\.]+\b)u.freeze # Word boundaries
+  SYMBOL        = %r((?:#{SYMBOL_BASE}|(?:<#{SYMBOL_BASE}>))(?!\s*::=))u.freeze
+  HEX           = %r(\#x\h+)u.freeze
+  CHAR          = %r([\u0009\u000A\u000D\u0020-\uD7FF\u{10000}-\u{10FFFF}])u.freeze
+  R_CHAR        = %r([\u0009\u000A\u000D\u0020-\u002C\u002E-\u005C\u005E-\uD7FF\u{10000}-\u{10FFFF}])u.freeze
+  LHS           = %r((?:\[#{SYMBOL_BASE}\])?\s*<?#{SYMBOL_BASE}>?\s*::=)u.freeze
+  BRKT          = %r((?:#{R_CHAR}\-#{R_CHAR})|(?:#{HEX}\-#{HEX})|#{R_CHAR}|#{HEX})u.freeze
+  BRKT_LEAD     = %r(-#{BRKT}+)u.freeze
+  BRKT_TRAIL    = %r(#{BRKT}+-?)u.freeze
+  RANGE         = %r(\[(?:#{BRKT_LEAD}|#{BRKT_TRAIL})\])u.freeze
+  RANGE_NOT_LHS = %r(\[(?:#{BRKT_LEAD}|#{BRKT_TRAIL})\](?!\s*<?#{SYMBOL_BASE}>?\s*::=))u.freeze
+  O_RANGE       = %r(\[\^(?:#{BRKT_LEAD}|#{BRKT_TRAIL})\])u.freeze
+  STRING1       = %r("[\u0009\u000A\u000D\u0020\u0021\u0023-\uD7FF\u{10000}-\u{10FFFF}]*")u.freeze
+  STRING2       = %r('[\u0009\u000A\u000D\u0020-\u0026\u0028-\uD7FF\u{10000}-\u{10FFFF}]*')u.freeze
+  POSTFIX       = %r([?*+])u.freeze
+  PASS          = %r((
     \s
   | (?:(?:\#[^x]|//)[^\n\r]*)
   | (?:/\*(?:(?:\*[^/])|[^*])*\*/)
diff --git a/spec/parser_spec.rb b/spec/parser_spec.rb
index db68f14..de11933 100644
--- a/spec/parser_spec.rb
+++ b/spec/parser_spec.rb
@@ -42,6 +42,14 @@
                 UCHAR))
               '>')))},
       ],
+      "range with leading hyphen": [
+        %{[14] PubidChar ::= [-'()+,./:=?;!*#@$_%]},
+        %{((terminal PubidChar "14" (range "-'()+,./:=?;!*#@$_%")))}
+      ],
+      "range with trailing hyphen": [
+        %{[14] PubidChar ::= ['()+,./:=?;!*#@$_%-]},
+        %{((terminal PubidChar "14" (range "'()+,./:=?;!*#@$_%-")))}
+      ],
       "minimal whitespace": [
         %{[xx]minimal::=whitespace[yy]whitespace::=" "},
         %{((rule minimal "xx" (seq whitespace))
@@ -111,6 +119,8 @@
       %{[#x20-#x22]} => %{(range "#x20-#x22")},
       %{[abc]} => %{(range "abc")},
       %{[abc-]} => %{(range "abc-")},
+      %{[-abc]} => %{(range "-abc")},
+      %{[-'()+,./:=?;!*#@$_%]} => %{(range "-'()+,./:=?;!*#@$_%")},
       %{[#x20#x21#x22]} => %{(range "#x20#x21#x22")},
       %{BaseDecl? PrefixDecl*} => %{(seq (opt BaseDecl) (star PrefixDecl))},
       %{NCCHAR1 | '-' | [0-9] | #x00B7 | [#x0300-#x036F] | [#x203F-#x2040]} =>
@@ -130,7 +140,8 @@
       "illegal rule name": %{$rule.name ::= foo},
       "diff missing second operand": %{rule ::= a -},
       "unrecognized terminal" => %{rule ::= %foo%},
-      "unopened paren" => %{rule ::= a) b c}
+      "unopened paren" => %{rule ::= a) b c},
+      "leading and trailing hyphen in range" => %{rule ::= [-abc-]}
     }.each do |title, input|
       it title do
         expect {parse(input)}.to raise_error(SyntaxError)
diff --git a/spec/rule_spec.rb b/spec/rule_spec.rb
index 7e6a269..3af8797 100644
--- a/spec/rule_spec.rb
+++ b/spec/rule_spec.rb
@@ -968,8 +968,20 @@
         "a ::= [#x20-b]",
         /Range contains illegal components/
       ],
-      "incomplete range": [
-        "a ::= [-b]",
+      "redundant '-' in range (one intervening)": [
+        "a ::= [-b-]",
+        /syntax error,/
+      ],
+      "redundant '-' in range (many intervening)": [
+        "a ::= [-def-]",
+        /syntax error,/
+      ],
+      "redundant '-' in range (one hex intervening)": [
+        "a ::= [-#x20-]",
+        /syntax error,/
+      ],
+      "redundant '-' in range (many hex intervening)": [
+        "a ::= [-#x20#x5b#x5c -]",
         /syntax error,/
       ],
       "extra range": [