Do not convert string to string

src/preserves.nim

@@ -34,12 +34,12 @@ proc len*(s: Symbol): int {.borrow.}
 
 proc `$`*(s: Symbol): string =
   let sym = string s
-  if sym.len > 0 and sym.string[0] in {'A'..'z'} and not sym.anyIt(char(it) in { '\x00'..'\x19', '"', '\\', '|' }):
-    result = string sym
+  if sym.len > 0 and sym[0] in {'A'..'z'} and not sym.anyIt(char(it) in { '\x00'..'\x19', '"', '\\', '|' }):
+    result = sym
   else:
     result = newStringOfCap(sym.len shl 1)
     result.add('|')
-    for c in sym.string:
+    for c in sym:
       case c
       of '\\':
         result.add("\\\\")