@ ProgramNode (location: (0...145))
├── locals: []
└── statements:
    @ StatementsNode (location: (0...145))
    └── body: (length: 3)
        ├── @ DefNode (location: (0...49))
        │   ├── name: :exec
        │   ├── name_loc: (9...13) = "exec"
        │   ├── receiver:
        │   │   @ SelfNode (location: (4...8))
        │   ├── parameters:
        │   │   @ ParametersNode (location: (14...17))
        │   │   ├── requireds: (length: 1)
        │   │   │   └── @ RequiredParameterNode (location: (14...17))
        │   │   │       └── name: :cmd
        │   │   ├── optionals: (length: 0)
        │   │   ├── rest: ∅
        │   │   ├── posts: (length: 0)
        │   │   ├── keywords: (length: 0)
        │   │   ├── keyword_rest: ∅
        │   │   └── block: ∅
        │   ├── body:
        │   │   @ BeginNode (location: (21...49))
        │   │   ├── begin_keyword_loc: ∅
        │   │   ├── statements:
        │   │   │   @ StatementsNode (location: (21...32))
        │   │   │   └── body: (length: 1)
        │   │   │       └── @ CallNode (location: (21...32))
        │   │   │           ├── receiver: ∅
        │   │   │           ├── call_operator_loc: ∅
        │   │   │           ├── message_loc: (21...27) = "system"
        │   │   │           ├── opening_loc: (27...28) = "("
        │   │   │           ├── arguments:
        │   │   │           │   @ ArgumentsNode (location: (28...31))
        │   │   │           │   └── arguments: (length: 1)
        │   │   │           │       └── @ LocalVariableReadNode (location: (28...31))
        │   │   │           │           ├── name: :cmd
        │   │   │           │           └── depth: 0
        │   │   │           ├── closing_loc: (31...32) = ")"
        │   │   │           ├── block: ∅
        │   │   │           ├── flags: ∅
        │   │   │           └── name: "system"
        │   │   ├── rescue_clause:
        │   │   │   @ RescueNode (location: (33...45))
        │   │   │   ├── keyword_loc: (33...39) = "rescue"
        │   │   │   ├── exceptions: (length: 0)
        │   │   │   ├── operator_loc: ∅
        │   │   │   ├── reference: ∅
        │   │   │   ├── statements:
        │   │   │   │   @ StatementsNode (location: (42...45))
        │   │   │   │   └── body: (length: 1)
        │   │   │   │       └── @ NilNode (location: (42...45))
        │   │   │   └── consequent: ∅
        │   │   ├── else_clause: ∅
        │   │   ├── ensure_clause: ∅
        │   │   └── end_keyword_loc: (46...49) = "end"
        │   ├── locals: [:cmd]
        │   ├── def_keyword_loc: (0...3) = "def"
        │   ├── operator_loc: (8...9) = "."
        │   ├── lparen_loc: (13...14) = "("
        │   ├── rparen_loc: (17...18) = ")"
        │   ├── equal_loc: ∅
        │   └── end_keyword_loc: (46...49) = "end"
        ├── @ DefNode (location: (52...99))
        │   ├── name: :exec
        │   ├── name_loc: (61...65) = "exec"
        │   ├── receiver:
        │   │   @ SelfNode (location: (56...60))
        │   ├── parameters:
        │   │   @ ParametersNode (location: (66...69))
        │   │   ├── requireds: (length: 1)
        │   │   │   └── @ RequiredParameterNode (location: (66...69))
        │   │   │       └── name: :cmd
        │   │   ├── optionals: (length: 0)
        │   │   ├── rest: ∅
        │   │   ├── posts: (length: 0)
        │   │   ├── keywords: (length: 0)
        │   │   ├── keyword_rest: ∅
        │   │   └── block: ∅
        │   ├── body:
        │   │   @ StatementsNode (location: (73...95))
        │   │   └── body: (length: 1)
        │   │       └── @ RescueModifierNode (location: (73...95))
        │   │           ├── expression:
        │   │           │   @ CallNode (location: (73...84))
        │   │           │   ├── receiver: ∅
        │   │           │   ├── call_operator_loc: ∅
        │   │           │   ├── message_loc: (73...79) = "system"
        │   │           │   ├── opening_loc: (79...80) = "("
        │   │           │   ├── arguments:
        │   │           │   │   @ ArgumentsNode (location: (80...83))
        │   │           │   │   └── arguments: (length: 1)
        │   │           │   │       └── @ LocalVariableReadNode (location: (80...83))
        │   │           │   │           ├── name: :cmd
        │   │           │   │           └── depth: 0
        │   │           │   ├── closing_loc: (83...84) = ")"
        │   │           │   ├── block: ∅
        │   │           │   ├── flags: ∅
        │   │           │   └── name: "system"
        │   │           ├── keyword_loc: (85...91) = "rescue"
        │   │           └── rescue_expression:
        │   │               @ NilNode (location: (92...95))
        │   ├── locals: [:cmd]
        │   ├── def_keyword_loc: (52...55) = "def"
        │   ├── operator_loc: (60...61) = "."
        │   ├── lparen_loc: (65...66) = "("
        │   ├── rparen_loc: (69...70) = ")"
        │   ├── equal_loc: ∅
        │   └── end_keyword_loc: (96...99) = "end"
        └── @ DefNode (location: (102...145))
            ├── name: :exec
            ├── name_loc: (111...115) = "exec"
            ├── receiver:
            │   @ SelfNode (location: (106...110))
            ├── parameters:
            │   @ ParametersNode (location: (116...119))
            │   ├── requireds: (length: 1)
            │   │   └── @ RequiredParameterNode (location: (116...119))
            │   │       └── name: :cmd
            │   ├── optionals: (length: 0)
            │   ├── rest: ∅
            │   ├── posts: (length: 0)
            │   ├── keywords: (length: 0)
            │   ├── keyword_rest: ∅
            │   └── block: ∅
            ├── body:
            │   @ StatementsNode (location: (123...145))
            │   └── body: (length: 1)
            │       └── @ RescueModifierNode (location: (123...145))
            │           ├── expression:
            │           │   @ CallNode (location: (123...134))
            │           │   ├── receiver: ∅
            │           │   ├── call_operator_loc: ∅
            │           │   ├── message_loc: (123...129) = "system"
            │           │   ├── opening_loc: (129...130) = "("
            │           │   ├── arguments:
            │           │   │   @ ArgumentsNode (location: (130...133))
            │           │   │   └── arguments: (length: 1)
            │           │   │       └── @ LocalVariableReadNode (location: (130...133))
            │           │   │           ├── name: :cmd
            │           │   │           └── depth: 0
            │           │   ├── closing_loc: (133...134) = ")"
            │           │   ├── block: ∅
            │           │   ├── flags: ∅
            │           │   └── name: "system"
            │           ├── keyword_loc: (135...141) = "rescue"
            │           └── rescue_expression:
            │               @ NilNode (location: (142...145))
            ├── locals: [:cmd]
            ├── def_keyword_loc: (102...105) = "def"
            ├── operator_loc: (110...111) = "."
            ├── lparen_loc: (115...116) = "("
            ├── rparen_loc: (119...120) = ")"
            ├── equal_loc: (121...122) = "="
            └── end_keyword_loc: ∅
