fddl examples.fddl 
Func
Identifier("main")
LeftParen
RightParen
LeftBrace
Comment(" print statement")
Print
LeftParen
StringLiteral("hello, world in fddl")
RightParen
Semicolon
Comment(" variable declaration")
Let
Identifier("y")
Equal
Number(5.0)
Semicolon
Comment(" if statement")
If
LeftParen
Identifier("x")
Greater
Number(10.0)
RightParen
LeftBrace
Print
LeftParen
StringLiteral("x is greater than 10")
RightParen
Semicolon
RightBrace
Comment(" while loop")
While
LeftParen
Identifier("x")
Less
Number(100.0)
RightParen
LeftBrace
Print
LeftParen
Identifier("x")
RightParen
Semicolon
Let
Identifier("x")
Equal
Identifier("x")
Plus
Number(1.0)
Semicolon
RightBrace
RightBrace
EOF
