{
    package main

    func main() {
    }
}

// any base64 input is good. force some backtracking.

File ← ( L S? / L N? / N L? / N S? / S L? / S N? ) File* EOF
L ← [a-z]i+
N ← [0-9]+
S ← [/+=]+
EOF ← !.
