@ ProgramNode (location: (1,0)-(1,8))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(1,8))
    └── body: (length: 1)
        └── @ ConstantWriteNode (location: (1,0)-(1,8))
            ├── name: :Foo
            ├── name_loc: (1,0)-(1,3) = "Foo"
            ├── value:
            │   @ IntegerNode (location: (1,6)-(1,8))
            │   ├── flags: decimal
            │   └── value: 10
            └── operator_loc: (1,4)-(1,5) = "="