FIRST sets
-----------------------------
FIRST(#1) = {'0'..'9'}

FIRST(#2) = {'?'}

FIRST(#3) = {e}




FOLLOW sets
-----------------------------
FOLLOW(Tern) = {':', $}

FOLLOW(TernTail) = FOLLOW(Tern) = {':', $}




FIRST+ sets
-----------------------------
FIRST+(#1) = FIRST(#1) = {'0'..'9'}

FIRST+(#2) = FIRST(#2) = {'?'}

// FIRST(#3) contains e
FIRST+(#3) = FIRST(#3) U FOLLOW(TernTail) \ {e} = {':', $}
