Clojure store persistent data structures gotcha – load-file size limit

In clojure – the data structure and their default representation are suited as readable and portable format to persist data. But there is a small pitfall in using it.

Data Structure example:

{
  :request-time 2636,
  :status 200,
  :headers
  {
    "server" "Server",
    "content-encoding" "gzip",
  }
}

Be aware that this function is intended to load code only. If your data structures or a string in them grow bigger than around 65,535 it crashes.

Exception similar to:

java.lang.ClassFormatError: Unknown constant tag 49 in class file parse$eval13

Please use read-string instead.

Example: (read-string (slurp "data.clj"))

Source: Rich Hickey on google groups Google Groups