@ ProgramNode (location: (1,0)-(12,4))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(12,4))
    └── body: (length: 2)
        ├── @ InterpolatedStringNode (location: (1,0)-(1,7))
        │   ├── flags: ∅
        │   ├── opening_loc: (1,0)-(1,7) = "<<~RUBY"
        │   ├── parts: (length: 4)
        │   │   ├── @ StringNode (location: (2,0)-(3,0))
        │   │   │   ├── flags: frozen
        │   │   │   ├── opening_loc: ∅
        │   │   │   ├── content_loc: (2,0)-(3,0) = "pre\n"
        │   │   │   ├── closing_loc: ∅
        │   │   │   └── unescaped: "pre\n"
        │   │   ├── @ EmbeddedStatementsNode (location: (3,0)-(7,1))
        │   │   │   ├── opening_loc: (3,0)-(3,2) = "\#{"
        │   │   │   ├── statements:
        │   │   │   │   @ StatementsNode (location: (4,0)-(4,6))
        │   │   │   │   └── body: (length: 1)
        │   │   │   │       └── @ StringNode (location: (4,0)-(4,6))
        │   │   │   │           ├── flags: ∅
        │   │   │   │           ├── opening_loc: (4,0)-(4,6) = "<<RUBY"
        │   │   │   │           ├── content_loc: (5,0)-(6,0) = "  hello\n"
        │   │   │   │           ├── closing_loc: (6,0)-(7,0) = "RUBY\n"
        │   │   │   │           └── unescaped: "  hello\n"
        │   │   │   └── closing_loc: (7,0)-(7,1) = "}"
        │   │   ├── @ StringNode (location: (7,1)-(8,0))
        │   │   │   ├── flags: frozen
        │   │   │   ├── opening_loc: ∅
        │   │   │   ├── content_loc: (7,1)-(8,0) = "\n"
        │   │   │   ├── closing_loc: ∅
        │   │   │   └── unescaped: "\n"
        │   │   └── @ StringNode (location: (8,0)-(9,0))
        │   │       ├── flags: frozen
        │   │       ├── opening_loc: ∅
        │   │       ├── content_loc: (8,0)-(9,0) = "post\n"
        │   │       ├── closing_loc: ∅
        │   │       └── unescaped: "post\n"
        │   └── closing_loc: (9,0)-(10,0) = "RUBY\n"
        └── @ InterpolatedStringNode (location: (12,0)-(12,4))
            ├── flags: ∅
            ├── opening_loc: (12,0)-(12,4) = "<<-A"
            ├── parts: (length: 2)
            │   ├── @ EmbeddedStatementsNode (location: (13,0)-(21,1))
            │   │   ├── opening_loc: (13,0)-(13,2) = "\#{"
            │   │   ├── statements:
            │   │   │   @ StatementsNode (location: (14,0)-(14,4))
            │   │   │   └── body: (length: 1)
            │   │   │       └── @ InterpolatedStringNode (location: (14,0)-(14,4))
            │   │   │           ├── flags: ∅
            │   │   │           ├── opening_loc: (14,0)-(14,4) = "<<-B"
            │   │   │           ├── parts: (length: 2)
            │   │   │           │   ├── @ EmbeddedStatementsNode (location: (15,0)-(19,1))
            │   │   │           │   │   ├── opening_loc: (15,0)-(15,2) = "\#{"
            │   │   │           │   │   ├── statements:
            │   │   │           │   │   │   @ StatementsNode (location: (16,0)-(16,4))
            │   │   │           │   │   │   └── body: (length: 1)
            │   │   │           │   │   │       └── @ InterpolatedStringNode (location: (16,0)-(16,4))
            │   │   │           │   │   │           ├── flags: ∅
            │   │   │           │   │   │           ├── opening_loc: (16,0)-(16,4) = "<<-C"
            │   │   │           │   │   │           ├── parts: (length: 2)
            │   │   │           │   │   │           │   ├── @ EmbeddedStatementsNode (location: (17,0)-(17,4))
            │   │   │           │   │   │           │   │   ├── opening_loc: (17,0)-(17,2) = "\#{"
            │   │   │           │   │   │           │   │   ├── statements:
            │   │   │           │   │   │           │   │   │   @ StatementsNode (location: (17,2)-(17,3))
            │   │   │           │   │   │           │   │   │   └── body: (length: 1)
            │   │   │           │   │   │           │   │   │       └── @ IntegerNode (location: (17,2)-(17,3))
            │   │   │           │   │   │           │   │   │           ├── flags: decimal
            │   │   │           │   │   │           │   │   │           └── value: 3
            │   │   │           │   │   │           │   │   └── closing_loc: (17,3)-(17,4) = "}"
            │   │   │           │   │   │           │   └── @ StringNode (location: (17,4)-(18,0))
            │   │   │           │   │   │           │       ├── flags: frozen
            │   │   │           │   │   │           │       ├── opening_loc: ∅
            │   │   │           │   │   │           │       ├── content_loc: (17,4)-(18,0) = "\n"
            │   │   │           │   │   │           │       ├── closing_loc: ∅
            │   │   │           │   │   │           │       └── unescaped: "\n"
            │   │   │           │   │   │           └── closing_loc: (18,0)-(19,0) = "C\n"
            │   │   │           │   │   └── closing_loc: (19,0)-(19,1) = "}"
            │   │   │           │   └── @ StringNode (location: (19,1)-(20,0))
            │   │   │           │       ├── flags: frozen
            │   │   │           │       ├── opening_loc: ∅
            │   │   │           │       ├── content_loc: (19,1)-(20,0) = "\n"
            │   │   │           │       ├── closing_loc: ∅
            │   │   │           │       └── unescaped: "\n"
            │   │   │           └── closing_loc: (20,0)-(21,0) = "B\n"
            │   │   └── closing_loc: (21,0)-(21,1) = "}"
            │   └── @ StringNode (location: (21,1)-(22,0))
            │       ├── flags: frozen
            │       ├── opening_loc: ∅
            │       ├── content_loc: (21,1)-(22,0) = "\n"
            │       ├── closing_loc: ∅
            │       └── unescaped: "\n"
            └── closing_loc: (22,0)-(23,0) = "A\n"