diff --git a/lib/compiler/passes/generate-js.js b/lib/compiler/passes/generate-js.js
index 301dc0f..3f9b5e3 100644
--- a/lib/compiler/passes/generate-js.js
+++ b/lib/compiler/passes/generate-js.js
@@ -781,6 +781,106 @@ function generateJS(ast, options) {
       '}',
       '',
       'peg$subclass(peg$SyntaxError, Error);',
+      '',
+      'peg$SyntaxError.buildMessage = function(expected, found) {',
+      '  var DESCRIBE_EXPECTATION_FNS = {',
+      '        literal: function(expectation) {',
+      '          return "\\\"" + literalEscape(expectation.text) + "\\\"";',
+      '        },',
+      '',
+      '        class: function(expectation) {',
+      '          var escapedParts = "",',
+      '              i;',
+      '',
+      '          for (i = 0; i < expectation.parts.length; i++) {',
+      '            escapedParts += expectation.parts[i] instanceof Array',
+      '              ? classEscape(expectation.parts[i][0]) + "-" + classEscape(expectation.parts[i][1])',
+      '              : classEscape(expectation.parts[i]);',
+      '          }',
+      '',
+      '          return "[" + (expectation.inverted ? "^" : "") + escapedParts + "]";',
+      '        },',
+      '',
+      '        any: function(expectation) {',
+      '          return "any character";',
+      '        },',
+      '',
+      '        end: function(expectation) {',
+      '          return "end of input";',
+      '        },',
+      '',
+      '        other: function(expectation) {',
+      '          return expectation.description;',
+      '        }',
+      '      };',
+      '',
+      '  function hex(ch) {',
+      '    return ch.charCodeAt(0).toString(16).toUpperCase();',
+      '  }',
+      '',
+      '  function literalEscape(s) {',
+      '    return s',
+      '      .replace(/\\\\/g, \'\\\\\\\\\')',   // backslash
+      '      .replace(/"/g,  \'\\\\"\')',        // closing double quote
+      '      .replace(/\\0/g, \'\\\\0\')',       // null
+      '      .replace(/\\t/g, \'\\\\t\')',       // horizontal tab
+      '      .replace(/\\n/g, \'\\\\n\')',       // line feed
+      '      .replace(/\\r/g, \'\\\\r\')',       // carriage return
+      '      .replace(/[\\x00-\\x0F]/g,          function(ch) { return \'\\\\x0\' + hex(ch); })',
+      '      .replace(/[\\x10-\\x1F\\x7F-\\x9F]/g, function(ch) { return \'\\\\x\'  + hex(ch); });',
+      '  }',
+      '',
+      '  function classEscape(s) {',
+      '    return s',
+      '      .replace(/\\\\/g, \'\\\\\\\\\')',   // backslash
+      '      .replace(/\\]/g, \'\\\\]\')',       // closing bracket
+      '      .replace(/\\^/g, \'\\\\^\')',       // caret
+      '      .replace(/-/g,  \'\\\\-\')',        // dash
+      '      .replace(/\\0/g, \'\\\\0\')',       // null
+      '      .replace(/\\t/g, \'\\\\t\')',       // horizontal tab
+      '      .replace(/\\n/g, \'\\\\n\')',       // line feed
+      '      .replace(/\\r/g, \'\\\\r\')',       // carriage return
+      '      .replace(/[\\x00-\\x0F]/g,          function(ch) { return \'\\\\x0\' + hex(ch); })',
+      '      .replace(/[\\x10-\\x1F\\x7F-\\x9F]/g, function(ch) { return \'\\\\x\'  + hex(ch); });',
+      '  }',
+      '',
+      '  function describeExpectation(expectation) {',
+      '    return DESCRIBE_EXPECTATION_FNS[expectation.type](expectation);',
+      '  }',
+      '',
+      '  function describeExpected(expected) {',
+      '    var descriptions = new Array(expected.length),',
+      '        i, j;',
+      '',
+      '    for (i = 0; i < expected.length; i++) {',
+      '      descriptions[i] = describeExpectation(expected[i]);',
+      '    }',
+      '',
+      '    descriptions.sort();',
+      '',
+      '    if (descriptions.length > 0) {',
+      '      for (i = 1, j = 1; i < descriptions.length; i++) {',
+      '        if (descriptions[i - 1] !== descriptions[i]) {',
+      '          descriptions[j] = descriptions[i];',
+      '          j++;',
+      '        }',
+      '      }',
+      '      descriptions.length = j;',
+      '    }',
+      '',
+      '    return descriptions.length > 1',
+      '      ? descriptions.slice(0, -1).join(", ")',
+      '          + " or "',
+      '          + descriptions[descriptions.length - 1]',
+      '      : descriptions[0];',
+      '  }',
+      '',
+      '  function describeFound(found) {',
+      '    return found ? "\\"" + literalEscape(found) + "\\"" : "end of input";',
+      '  }',
+      '',
+      '  return "Expected " + describeExpected(expected) + " but " + describeFound(found) + " found.";',
+      '};',
       ''
     ].join('\n'));
 
@@ -1045,108 +1145,8 @@ function generateJS(ast, options) {
       '  }',
       '',
       '  function peg$buildException(message, expected, found, location) {',
-      '    function buildMessage(expected, found) {',
-      '      var DESCRIBE_EXPECTATION_FNS = {',
-      '            literal: function(expectation) {',
-      '              return "\\\"" + literalEscape(expectation.text) + "\\\"";',
-      '            },',
-      '',
-      '            class: function(expectation) {',
-      '              var escapedParts = "",',
-      '                  i;',
-      '',
-      '              for (i = 0; i < expectation.parts.length; i++) {',
-      '                escapedParts += expectation.parts[i] instanceof Array',
-      '                  ? classEscape(expectation.parts[i][0]) + "-" + classEscape(expectation.parts[i][1])',
-      '                  : classEscape(expectation.parts[i]);',
-      '              }',
-      '',
-      '              return "[" + (expectation.inverted ? "^" : "") + escapedParts + "]";',
-      '            },',
-      '',
-      '            any: function(expectation) {',
-      '              return "any character";',
-      '            },',
-      '',
-      '            end: function(expectation) {',
-      '              return "end of input";',
-      '            },',
-      '',
-      '            other: function(expectation) {',
-      '              return expectation.description;',
-      '            }',
-      '          };',
-      '',
-      '      function hex(ch) {',
-      '        return ch.charCodeAt(0).toString(16).toUpperCase();',
-      '      }',
-      '',
-      '      function literalEscape(s) {',
-      '        return s',
-      '          .replace(/\\\\/g, \'\\\\\\\\\')',   // backslash
-      '          .replace(/"/g,  \'\\\\"\')',        // closing double quote
-      '          .replace(/\\0/g, \'\\\\0\')',       // null
-      '          .replace(/\\t/g, \'\\\\t\')',       // horizontal tab
-      '          .replace(/\\n/g, \'\\\\n\')',       // line feed
-      '          .replace(/\\r/g, \'\\\\r\')',       // carriage return
-      '          .replace(/[\\x00-\\x0F]/g,          function(ch) { return \'\\\\x0\' + hex(ch); })',
-      '          .replace(/[\\x10-\\x1F\\x7F-\\x9F]/g, function(ch) { return \'\\\\x\'  + hex(ch); });',
-      '      }',
-      '',
-      '      function classEscape(s) {',
-      '        return s',
-      '          .replace(/\\\\/g, \'\\\\\\\\\')',   // backslash
-      '          .replace(/\\]/g, \'\\\\]\')',       // closing bracket
-      '          .replace(/\\^/g, \'\\\\^\')',       // caret
-      '          .replace(/-/g,  \'\\\\-\')',        // dash
-      '          .replace(/\\0/g, \'\\\\0\')',       // null
-      '          .replace(/\\t/g, \'\\\\t\')',       // horizontal tab
-      '          .replace(/\\n/g, \'\\\\n\')',       // line feed
-      '          .replace(/\\r/g, \'\\\\r\')',       // carriage return
-      '          .replace(/[\\x00-\\x0F]/g,          function(ch) { return \'\\\\x0\' + hex(ch); })',
-      '          .replace(/[\\x10-\\x1F\\x7F-\\x9F]/g, function(ch) { return \'\\\\x\'  + hex(ch); });',
-      '      }',
-      '',
-      '      function describeExpectation(expectation) {',
-      '        return DESCRIBE_EXPECTATION_FNS[expectation.type](expectation);',
-      '      }',
-      '',
-      '      function describeExpected(expected) {',
-      '        var descriptions = new Array(expected.length),',
-      '            i, j;',
-      '',
-      '        for (i = 0; i < expected.length; i++) {',
-      '          descriptions[i] = describeExpectation(expected[i]);',
-      '        }',
-      '',
-      '        descriptions.sort();',
-      '',
-      '        if (descriptions.length > 0) {',
-      '          for (i = 1, j = 1; i < descriptions.length; i++) {',
-      '            if (descriptions[i - 1] !== descriptions[i]) {',
-      '              descriptions[j] = descriptions[i];',
-      '              j++;',
-      '            }',
-      '          }',
-      '          descriptions.length = j;',
-      '        }',
-      '',
-      '        return descriptions.length > 1',
-      '          ? descriptions.slice(0, -1).join(", ")',
-      '              + " or "',
-      '              + descriptions[descriptions.length - 1]',
-      '          : descriptions[0];',
-      '      }',
-      '',
-      '      function describeFound(found) {',
-      '        return found ? "\\"" + literalEscape(found) + "\\"" : "end of input";',
-      '      }',
-      '',
-      '      return "Expected " + describeExpected(expected) + " but " + describeFound(found) + " found.";',
-      '    }',
-      '',
       '    return new peg$SyntaxError(',
-      '      message !== null ? message : buildMessage(expected, found),',
+      '      message !== null ? message : peg$SyntaxError.buildMessage(expected, found),',
       '      expected,',
       '      found,',
       '      location',