diff --git a/examples/css.pegjs b/examples/css.pegjs
index 5a8bd07..5593d3c 100644
--- a/examples/css.pegjs
+++ b/examples/css.pegjs
@@ -180,7 +180,7 @@ simple_selector
     }
 
 class
-  = "." class:IDENT { return { type: "class_selector", "class": class }; }
+  = "." class_:IDENT { return { type: "class_selector", "class": class_ }; }
 
 element_name
   = IDENT / '*'
@@ -298,7 +298,7 @@ unicode
 
 escape
   = unicode
-  / "\\" char:[^\r\n\f0-9a-fA-F] { return char; }
+  / "\\" char_:[^\r\n\f0-9a-fA-F] { return char_; }
 
 nmstart
   = [_a-zA-Z]
@@ -386,91 +386,91 @@ G
   = [gG]
   / "\\" "0"? "0"? "0"? "0"? "47" ("\r\n" / [ \t\r\n\f])? { return "G"; }
   / "\\" "0"? "0"? "0"? "0"? "67" ("\r\n" / [ \t\r\n\f])? { return "g"; }
-  / "\\" char:[gG] { return char; }
+  / "\\" char_:[gG] { return char_; }
 
 H
   = h:[hH]
   / "\\" "0"? "0"? "0"? "0"? "48" ("\r\n" / [ \t\r\n\f])? { return "H"; }
   / "\\" "0"? "0"? "0"? "0"? "68" ("\r\n" / [ \t\r\n\f])? { return "h"; }
-  / "\\" char:[hH] { return char; }
+  / "\\" char_:[hH] { return char_; }
 
 I
   = i:[iI]
   / "\\" "0"? "0"? "0"? "0"? "49" ("\r\n" / [ \t\r\n\f])? { return "I"; }
   / "\\" "0"? "0"? "0"? "0"? "69" ("\r\n" / [ \t\r\n\f])? { return "i"; }
-  / "\\" char:[iI] { return char; }
+  / "\\" char_:[iI] { return char_; }
 
 K
   = [kK]
   / "\\" "0"? "0"? "0"? "0"? "4" [bB] ("\r\n" / [ \t\r\n\f])? { return "K"; }
   / "\\" "0"? "0"? "0"? "0"? "6" [bB] ("\r\n" / [ \t\r\n\f])? { return "k"; }
-  / "\\" char:[kK] { return char; }
+  / "\\" char_:[kK] { return char_; }
 
 L
   = [lL]
   / "\\" "0"? "0"? "0"? "0"? "4" [cC] ("\r\n" / [ \t\r\n\f])? { return "L"; }
   / "\\" "0"? "0"? "0"? "0"? "6" [cC] ("\r\n" / [ \t\r\n\f])? { return "l"; }
-  / "\\" char:[lL] { return char; }
+  / "\\" char_:[lL] { return char_; }
 
 M
   = [mM]
   / "\\" "0"? "0"? "0"? "0"? "4" [dD] ("\r\n" / [ \t\r\n\f])? { return "M"; }
   / "\\" "0"? "0"? "0"? "0"? "6" [dD] ("\r\n" / [ \t\r\n\f])? { return "m"; }
-  / "\\" char:[mM] { return char; }
+  / "\\" char_:[mM] { return char_; }
 
 N
   = [nN]
   / "\\" "0"? "0"? "0"? "0"? "4" [eE] ("\r\n" / [ \t\r\n\f])? { return "N"; }
   / "\\" "0"? "0"? "0"? "0"? "6" [eE] ("\r\n" / [ \t\r\n\f])? { return "n"; }
-  / "\\" char:[nN] { return char; }
+  / "\\" char_:[nN] { return char_; }
 
 O
   = [oO]
   / "\\" "0"? "0"? "0"? "0"? "4" [fF] ("\r\n" / [ \t\r\n\f])? { return "O"; }
   / "\\" "0"? "0"? "0"? "0"? "6" [fF] ("\r\n" / [ \t\r\n\f])? { return "o"; }
-  / "\\" char:[oO] { return char; }
+  / "\\" char_:[oO] { return char_; }
 
 P
   = [pP]
   / "\\" "0"? "0"? "0"? "0"? "50" ("\r\n" / [ \t\r\n\f])? { return "P"; }
   / "\\" "0"? "0"? "0"? "0"? "70" ("\r\n" / [ \t\r\n\f])? { return "p"; }
-  / "\\" char:[pP] { return char; }
+  / "\\" char_:[pP] { return char_; }
 
 R
   = [rR]
   / "\\" "0"? "0"? "0"? "0"? "52" ("\r\n" / [ \t\r\n\f])? { return "R"; }
   / "\\" "0"? "0"? "0"? "0"? "72" ("\r\n" / [ \t\r\n\f])? { return "r"; }
-  / "\\" char:[rR] { return char; }
+  / "\\" char_:[rR] { return char_; }
 
 S_
   = [sS]
   / "\\" "0"? "0"? "0"? "0"? "53" ("\r\n" / [ \t\r\n\f])? { return "S"; }
   / "\\" "0"? "0"? "0"? "0"? "73" ("\r\n" / [ \t\r\n\f])? { return "s"; }
-  / "\\" char:[sS] { return char; }
+  / "\\" char_:[sS] { return char_; }
 
 T
   = [tT]
   / "\\" "0"? "0"? "0"? "0"? "54" ("\r\n" / [ \t\r\n\f])? { return "T"; }
   / "\\" "0"? "0"? "0"? "0"? "74" ("\r\n" / [ \t\r\n\f])? { return "t"; }
-  / "\\" char:[tT] { return char; }
+  / "\\" char_:[tT] { return char_; }
 
 U
   = [uU]
   / "\\" "0"? "0"? "0"? "0"? "55" ("\r\n" / [ \t\r\n\f])? { return "U"; }
   / "\\" "0"? "0"? "0"? "0"? "75" ("\r\n" / [ \t\r\n\f])? { return "u"; }
-  / "\\" char:[uU] { return char; }
+  / "\\" char_:[uU] { return char_; }
 
 X
   = [xX]
   / "\\" "0"? "0"? "0"? "0"? "58" ("\r\n" / [ \t\r\n\f])? { return "X"; }
   / "\\" "0"? "0"? "0"? "0"? "78" ("\r\n" / [ \t\r\n\f])? { return "x"; }
-  / "\\" char:[xX] { return char; }
+  / "\\" char_:[xX] { return char_; }
 
 Z
   = [zZ]
   / "\\" "0"? "0"? "0"? "0"? "5" [aA] ("\r\n" / [ \t\r\n\f])? { return "Z"; }
   / "\\" "0"? "0"? "0"? "0"? "7" [aA] ("\r\n" / [ \t\r\n\f])? { return "z"; }
-  / "\\" char:[zZ] { return char; }
+  / "\\" char_:[zZ] { return char_; }
 
 /* Tokens */
 
diff --git a/examples/javascript.pegjs b/examples/javascript.pegjs
index 1de4bd0..7ae3150 100644
--- a/examples/javascript.pegjs
+++ b/examples/javascript.pegjs
@@ -257,13 +257,13 @@ SingleStringCharacters
   = chars:SingleStringCharacter+ { return chars.join(""); }
 
 DoubleStringCharacter
-  = !('"' / "\\" / LineTerminator) char:SourceCharacter { return char;     }
-  / "\\" sequence:EscapeSequence                        { return sequence; }
+  = !('"' / "\\" / LineTerminator) char_:SourceCharacter { return char_;     }
+  / "\\" sequence:EscapeSequence                         { return sequence;  }
   / LineContinuation
 
 SingleStringCharacter
-  = !("'" / "\\" / LineTerminator) char:SourceCharacter { return char;     }
-  / "\\" sequence:EscapeSequence                        { return sequence; }
+  = !("'" / "\\" / LineTerminator) char_:SourceCharacter { return char_;     }
+  / "\\" sequence:EscapeSequence                         { return sequence;  }
   / LineContinuation
 
 LineContinuation
@@ -280,8 +280,8 @@ CharacterEscapeSequence
   / NonEscapeCharacter
 
 SingleEscapeCharacter
-  = char:['"\\bfnrtv] {
-      return char
+  = char_:['"\\bfnrtv] {
+      return char_
         .replace("b", "\b")
         .replace("f", "\f")
         .replace("n", "\n")
@@ -291,7 +291,7 @@ SingleEscapeCharacter
     }
 
 NonEscapeCharacter
-  = (!EscapeCharacter / LineTerminator) char:SourceCharacter { return char; }
+  = (!EscapeCharacter / LineTerminator) char_:SourceCharacter { return char_; }
 
 EscapeCharacter
   = SingleEscapeCharacter
@@ -319,20 +319,20 @@ RegularExpressionLiteral "regular expression"
     }
 
 RegularExpressionBody
-  = char:RegularExpressionFirstChar chars:RegularExpressionChars {
-      return char + chars;
+  = char_:RegularExpressionFirstChar chars:RegularExpressionChars {
+      return char_ + chars;
     }
 
 RegularExpressionChars
   = chars:RegularExpressionChar* { return chars.join(""); }
 
 RegularExpressionFirstChar
-  = ![*\\/[] char:RegularExpressionNonTerminator { return char; }
+  = ![*\\/[] char_:RegularExpressionNonTerminator { return char_; }
   / RegularExpressionBackslashSequence
   / RegularExpressionClass
 
 RegularExpressionChar
-  = ![\\/[] char:RegularExpressionNonTerminator { return char; }
+  = ![\\/[] char_:RegularExpressionNonTerminator { return char_; }
   / RegularExpressionBackslashSequence
   / RegularExpressionClass
 
@@ -341,10 +341,10 @@ RegularExpressionChar
  * "RegularExpressionNonTerminator".
  */
 RegularExpressionBackslashSequence
-  = "\\" char:RegularExpressionNonTerminator { return "\\" + char; }
+  = "\\" char_:RegularExpressionNonTerminator { return "\\" + char_; }
 
 RegularExpressionNonTerminator
-  = !LineTerminator char:SourceCharacter { return char; }
+  = !LineTerminator char_:SourceCharacter { return char_; }
 
 RegularExpressionClass
   = "[" chars:RegularExpressionClassChars "]" { return "[" + chars + "]"; }
@@ -353,7 +353,7 @@ RegularExpressionClassChars
   = chars:RegularExpressionClassChar* { return chars.join(""); }
 
 RegularExpressionClassChar
-  = ![\]\\] char:RegularExpressionNonTerminator { return char; }
+  = ![\]\\] char_:RegularExpressionNonTerminator { return char_; }
   / RegularExpressionBackslashSequence
 
 RegularExpressionFlags
diff --git a/examples/json.pegjs b/examples/json.pegjs
index 0e06fc1..f2a34b1 100644
--- a/examples/json.pegjs
+++ b/examples/json.pegjs
@@ -70,10 +70,10 @@ char
     }
 
 number "number"
-  = int:int frac:frac exp:exp _ { return parseFloat(int + frac + exp); }
-  / int:int frac:frac _         { return parseFloat(int + frac);       }
-  / int:int exp:exp _           { return parseFloat(int + exp);        }
-  / int:int _                   { return parseFloat(int);              }
+  = int_:int frac:frac exp:exp _ { return parseFloat(int_ + frac + exp); }
+  / int_:int frac:frac _         { return parseFloat(int_ + frac);       }
+  / int_:int exp:exp _           { return parseFloat(int_ + exp);        }
+  / int_:int _                   { return parseFloat(int_);              }
 
 int
   = digit19:digit19 digits:digits     { return digit19 + digits;       }