diff --git a/lib/lexer.js b/lib/lexer.js
index 5d23d077..027d3e33 100644
--- a/lib/lexer.js
+++ b/lib/lexer.js
@@ -569,8 +569,8 @@
       return str.replace(MULTILINER, heredoc ? '\\n' : '');
     };
     Lexer.prototype.makeString = function(body, quote, heredoc) {
-      body = body.replace(/\\([\s\S])/g, function($amp, $1) {
-        return ('\n' === $1 || quote === $1) ? $1 : $amp;
+      body = body.replace(/\\([\s\S])/g, function(match, contents) {
+        return ('\n' === contents || quote === contents) ? contents : match;
       });
       body = body.replace(RegExp("" + quote, "g"), '\\$&');
       return quote + this.escapeLines(body, heredoc) + quote;
diff --git a/src/lexer.coffee b/src/lexer.coffee
index c7cf730b..4f411cb5 100644
--- a/src/lexer.coffee
+++ b/src/lexer.coffee
@@ -490,8 +490,8 @@ exports.Lexer = class Lexer
 
   # Constructs a string token by escaping quotes and newlines.
   makeString: (body, quote, heredoc) ->
-    body = body.replace /\\([\s\S])/g, ($amp, $1) ->
-      if $1 in ['\n', quote] then $1 else $amp
+    body = body.replace /\\([\s\S])/g, (match, contents) ->
+      if contents in ['\n', quote] then contents else match
     body = body.replace /// #{quote} ///g, '\\$&'
     quote + @escapeLines(body, heredoc) + quote