You’re asking it to parse the JSON text something (not "something"). That’s invalid JSON, strings must be in double quotes.
If you want an equivalent to your first example:
var s=""something"";
var result = JSON.parse(s);
You’re asking it to parse the JSON text something (not "something"). That’s invalid JSON, strings must be in double quotes.
If you want an equivalent to your first example:
var s=""something"";
var result = JSON.parse(s);