Fix unescaping of strings for factor

factor/lib/reader/reader.factor

@@ -1,18 +1,26 @@
 ! Copyright (C) 2015 Jordan Lewis.
 ! See http://factorcode.org/license.txt for BSD license.
-USING: arrays combinators grouping hashtables kernel lists
-locals make lib.types math.parser regexp sequences splitting ;
+USING: arrays combinators grouping hashtables kernel lists locals
+make lib.types math.parser regexp sequences splitting strings ;
 IN: lib.reader
 
 CONSTANT: token-regex R/ (~@|[\[\]{}()'`~^@]|"(?:\\.|[^\\"])*"|;.*|[^\s\[\]{}('"`,;)~^@]+)/
 
 DEFER: read-form
 
+: (read-string) ( str -- maltype )
+    rest but-last R/ \\./ [
+        {
+            { [ dup >string "\\\\" = ] [ drop "\\" ] }
+            { [ dup >string "\\n"  = ] [ drop "\n" ] }
+            { [ dup >string "\\\"" = ] [ drop "\"" ] }
+            [ ]
+        } cond
+    ] re-replace-with ;
+
 : (read-atom) ( str -- maltype )
     {
-        { [ dup first CHAR: " = ] [ rest but-last "\\\"" "\"" replace
-                                                  "\\n"  "\n" replace
-                                                  "\\\\" "\\" replace ] }
+        { [ dup first CHAR: " = ] [ (read-string) ] }
         { [ dup first CHAR: : = ] [ rest <malkeyword> ] }
         { [ dup "false" = ]       [ drop f ] }
         { [ dup "true" = ]        [ drop t ] }