Error in your example code about json-sans-eval HOT 5 OPEN

Quite right.  Fixed.

I'm not sure quite what you mean by reading a file.
Javascript does not expose file system bindings.
I could try including an example using common libraries XmlHttpRequest wrappers 
to
fetch a file from the web.

I guess what I meant was to show folks how javascript might read in the JSON 
string
from an external file into your 'myJson' string, so you can manipulate it 
through
your jsonParse function, instead of just assuming the user has access to the 
string
data to begin with.

At our company, we developed an excellent function that reads individual Json
elements from an external file source, but it doesn't use your jsonParse 
function.  

Here's how we do it.  Assuming you control the remote json file to begin with, 
then
you can cause the json data on that remote page to be written surrounded by a
javascript function, so that it appears on the page like this:

   MyJsonData({ "x": "Hello, World!", "y": [1, 2, 3] });

Then, on the internal page where you need to 'read' the remote json data, you 
can put
the following javascript code:

   var headerID = document.getElementsByTagName("head")[0];         
   var InScript = document.createElement('script');
   InScript.type = 'text/javascript';
   InScript.src = "path to your remote json file";
   headerID.appendChild(InScript);

   function MyJsonData(data)
   {
    var ret_x = data.x;
   }

When the json page is loaded into the current page's header, it's MyJsonData() 
data
contents become readable by the MyJsonData(data) function on this page, and the
individual json elements can then be accessed as data.x, data.y, etc.  

What I'd like to see is how your jsonParse might be integrated within a similar
'read' function, so that the entire string can be read into your myJson 
variable from
an external json-formatted file, and then parsed using your jsonParse function.

Excellent work on your code though!

Ok, so you used the word file to mean chunk of data, not a physical file on 
storage
media.

Is the scheme you're describing similar to JSONP :
http://en.wikipedia.org/wiki/JSON#JSONP ?

{'key':'abcd\r\nefghigklmnop\nqrstuvwxyz'}

How to do?

That is not valid JSON.  JSON only allows double quotes.

From htto://json.org/ :
  string
    ""
    " chars "