@ ProgramNode (location: (1,0)-(3,11))
├── locals: [:a]
└── statements:
    @ StatementsNode (location: (1,0)-(3,11))
    └── body: (length: 4)
        ├── @ MatchRequiredNode (location: (1,0)-(1,8))
        │   ├── value:
        │   │   @ IntegerNode (location: (1,0)-(1,1))
        │   │   ├── flags: decimal
        │   │   └── value: 1
        │   ├── pattern:
        │   │   @ ArrayPatternNode (location: (1,5)-(1,8))
        │   │   ├── constant: ∅
        │   │   ├── requireds: (length: 1)
        │   │   │   └── @ LocalVariableTargetNode (location: (1,6)-(1,7))
        │   │   │       ├── name: :a
        │   │   │       └── depth: 0
        │   │   ├── rest: ∅
        │   │   ├── posts: (length: 0)
        │   │   ├── opening_loc: (1,5)-(1,6) = "["
        │   │   └── closing_loc: (1,7)-(1,8) = "]"
        │   └── operator_loc: (1,2)-(1,4) = "=>"
        ├── @ LocalVariableReadNode (location: (1,10)-(1,11))
        │   ├── name: :a
        │   └── depth: 0
        ├── @ MatchPredicateNode (location: (3,0)-(3,8))
        │   ├── value:
        │   │   @ IntegerNode (location: (3,0)-(3,1))
        │   │   ├── flags: decimal
        │   │   └── value: 1
        │   ├── pattern:
        │   │   @ ArrayPatternNode (location: (3,5)-(3,8))
        │   │   ├── constant: ∅
        │   │   ├── requireds: (length: 1)
        │   │   │   └── @ LocalVariableTargetNode (location: (3,6)-(3,7))
        │   │   │       ├── name: :a
        │   │   │       └── depth: 0
        │   │   ├── rest: ∅
        │   │   ├── posts: (length: 0)
        │   │   ├── opening_loc: (3,5)-(3,6) = "["
        │   │   └── closing_loc: (3,7)-(3,8) = "]"
        │   └── operator_loc: (3,2)-(3,4) = "in"
        └── @ LocalVariableReadNode (location: (3,10)-(3,11))
            ├── name: :a
            └── depth: 0