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### 4.2 rfc2231

RFC2231 defines a syntax for the `Content-Type` and `Content-Disposition` headers. Its snappy name is MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations.

In short, these headers look something like this:

         Content-Type: application/x-stuff;
          title*0*=us-ascii'en'This%20is%20even%20more%20;
          title*1*=%2A%2A%2Afun%2A%2A%2A%20;
          title*2="isn't it!"

They usually aren't this bad, though.

The following functions are defined by this library:

`rfc2231-parse-string`
  Parse a `Content-Type` header and return a list describing its elements.

                (rfc2231-parse-string
                 "application/x-stuff;
                 title*0*=us-ascii'en'This%20is%20even%20more%20;
                 title*1*=%2A%2A%2Afun%2A%2A%2A%20;
                 title*2=\"isn't it!\"")
                ⇒ ("application/x-stuff"
                    (title . "This is even more ***fun*** isn't it!"))

`rfc2231-get-value`
  Takes one of the lists on the format above and returns the value of the specified attribute.
`rfc2231-encode-string`
  Encode a parameter in headers likes `Content-Type` and `Content-Disposition`.