diff --git a/lib/lexer.js b/lib/lexer.js
index a4954b2b..f9f9a009 100644
--- a/lib/lexer.js
+++ b/lib/lexer.js
@@ -149,7 +149,9 @@
       doc = this.sanitizeHeredoc(match[2] || match[4], {
         quote: quote
       });
-      this.interpolateString(("" + quote + doc + quote), false, true);
+      this.interpolateString(("" + quote + doc + quote), {
+        heredoc: true
+      });
       this.line += count(match[1], "\n");
       this.i += match[1].length;
       return true;
@@ -205,7 +207,9 @@
           return '\\' + escaped;
         });
         this.tokens = this.tokens.concat([['(', '('], ['NEW', 'new'], ['IDENTIFIER', 'RegExp'], ['CALL_START', '(']]);
-        this.interpolateString(("\"" + str + "\""), true);
+        this.interpolateString(("\"" + str + "\""), {
+          escapeQuotes: true
+        });
         if (flags) {
           this.tokens.splice(this.tokens.length, 0, [',', ','], ['STRING', ("\"" + flags + "\"")]);
         }
@@ -453,8 +457,9 @@
       }
       return !i ? false : str.substring(0, i);
     };
-    Lexer.prototype.interpolateString = function(str, escapeQuotes, heredoc) {
+    Lexer.prototype.interpolateString = function(str, options) {
       var _d, _e, _f, _g, _h, _i, _j, escaped, expr, group, i, idx, inner, interp, interpolated, lexer, match, nested, pi, quote, tag, tok, token, tokens, value;
+      options = options || {};
       if (str.length < 3 || !starts(str, '"')) {
         return this.token('STRING', str);
       } else {
@@ -486,7 +491,7 @@
             }
             inner = expr.substring(2, expr.length - 1);
             if (inner.length) {
-              if (heredoc) {
+              if (options.heredoc) {
                 inner = inner.replace(new RegExp('\\\\' + quote, 'g'), quote);
               }
               nested = lexer.tokenize(("(" + inner + ")"), {
@@ -525,7 +530,7 @@
           value = _j[1];
           if (tag === 'TOKENS') {
             this.tokens = this.tokens.concat(value);
-          } else if (tag === 'STRING' && escapeQuotes) {
+          } else if (tag === 'STRING' && options.escapeQuotes) {
             escaped = value.substring(1, value.length - 1).replace(/"/g, '\\"');
             this.token(tag, ("\"" + escaped + "\""));
           } else {
diff --git a/src/lexer.coffee b/src/lexer.coffee
index ae224796..80da3fef 100644
--- a/src/lexer.coffee
+++ b/src/lexer.coffee
@@ -132,7 +132,7 @@ exports.Lexer: class Lexer
     return false unless match: @chunk.match(HEREDOC)
     quote: match[1].substr 0, 1
     doc: @sanitizeHeredoc match[2] or match[4], {quote}
-    @interpolateString "$quote$doc$quote", no, yes
+    @interpolateString "$quote$doc$quote", {heredoc: yes}
     @line: + count match[1], "\n"
     @i: + match[1].length
     true
@@ -170,7 +170,7 @@ exports.Lexer: class Lexer
       str: regex.substring(1).split('/')[0]
       str: str.replace REGEX_ESCAPE, (escaped) -> '\\' + escaped
       @tokens: @tokens.concat [['(', '('], ['NEW', 'new'], ['IDENTIFIER', 'RegExp'], ['CALL_START', '(']]
-      @interpolateString "\"$str\"", yes
+      @interpolateString "\"$str\"", {escapeQuotes: yes}
       @tokens.splice @tokens.length, 0, [',', ','], ['STRING', "\"$flags\""] if flags
       @tokens.splice @tokens.length, 0, [')', ')'], [')', ')']
     else
@@ -389,7 +389,8 @@ exports.Lexer: class Lexer
   # If it encounters an interpolation, this method will recursively create a
   # new Lexer, tokenize the interpolated contents, and merge them into the
   # token stream.
-  interpolateString: (str, escapeQuotes, heredoc) ->
+  interpolateString: (str, options) ->
+    options: or {}
     if str.length < 3 or not starts str, '"'
       @token 'STRING', str
     else
@@ -411,7 +412,7 @@ exports.Lexer: class Lexer
           tokens.push ['STRING', "$quote${ str.substring(pi, i) }$quote"] if pi < i
           inner: expr.substring(2, expr.length - 1)
           if inner.length
-            inner: inner.replace new RegExp('\\\\' + quote, 'g'), quote if heredoc
+            inner: inner.replace new RegExp('\\\\' + quote, 'g'), quote if options.heredoc
             nested: lexer.tokenize "($inner)", {line: @line}
             (tok[0]: ')') for tok, idx in nested when tok[0] is 'CALL_END'
             nested.pop()
@@ -429,7 +430,7 @@ exports.Lexer: class Lexer
         [tag, value]: token
         if tag is 'TOKENS'
           @tokens: @tokens.concat value
-        else if tag is 'STRING' and escapeQuotes
+        else if tag is 'STRING' and options.escapeQuotes
           escaped: value.substring(1, value.length - 1).replace(/"/g, '\\"')
           @token tag, "\"$escaped\""
         else