(command.CommandList
  children: [
    (command.Simple
      blame_tok: <_Dbg_help_add_sub>
      more_env: []
      words: [{<_Dbg_help_add_sub>} {<show>} {<tty>} {(DQ <'Show tty used for debugger output'>)} {<1>}]
      redirects: []
      do_fork: T
    )
    (command.ShFunction
      name_tok: <_Dbg_do_show_tty>
      name: _Dbg_do_show_tty
      body: 
        (BraceGroup
          left: <Id.Lit_LBrace '{'>
          children: [
            (command.Simple
              blame_tok: <typeset>
              more_env: []
              words: [{<typeset>} {<label>}]
              redirects: []
              do_fork: T
            )
            (command.AndOr
              children: [
                (command.DBracket
                  left: <Id.KW_DLeftBracket '[['>
                  expr: (bool_expr.Unary op_id:Id.BoolUnary_n child:{($ Id.VSub_Number 1)})
                  right: <Id.Lit_DRightBracket ']]'>
                  redirects: []
                )
                (command.ShAssignment
                  left: <Id.Lit_VarLike 'label='>
                  pairs: [
                    (AssignPair
                      left: <Id.Lit_VarLike 'label='>
                      lhs: (sh_lhs_expr.Name left:<Id.Lit_VarLike 'label='> name:label)
                      op: assign_op.Equal
                      rhs: 
                        {
                          (CommandSub
                            left_token: <Id.Left_DollarParen '$('>
                            child: 
                              (command.Simple
                                blame_tok: <builtin>
                                more_env: []
                                words: [{<builtin>} {<printf>} {(SQ <'%-12s: '>)} {(SQ <'show tty'>)}]
                                redirects: []
                                do_fork: T
                              )
                            right: <Id.Eof_RParen _>
                          )
                        }
                    )
                  ]
                  redirects: []
                )
                (command.ShAssignment
                  left: <Id.Lit_VarLike 'label='>
                  pairs: [
                    (AssignPair
                      left: <Id.Lit_VarLike 'label='>
                      lhs: (sh_lhs_expr.Name left:<Id.Lit_VarLike 'label='> name:label)
                      op: assign_op.Equal
                      rhs: {(SQ )}
                    )
                  ]
                  redirects: []
                )
              ]
              ops: [<Id.Op_DAmp _> <Id.Op_DPipe _>]
            )
            (command.Simple
              blame_tok: <_Dbg_msg_nocr>
              more_env: []
              words: [{<_Dbg_msg_nocr>} {(DQ (${ Id.VSub_Name label) <'Debugger output goes to '>)}]
              redirects: []
              do_fork: T
            )
            (command.If
              if_kw: <Id.KW_If if>
              arms: [
                (IfArm
                  keyword: <Id.KW_If if>
                  cond: 
                    (condition.Shell
                      commands: [
                        (command.Sentence
                          child: 
                            (command.DBracket
                              left: <Id.KW_DLeftBracket '[['>
                              expr: 
                                (bool_expr.Unary
                                  op_id: Id.BoolUnary_n
                                  child: {($ Id.VSub_DollarName _Dbg_tty)}
                                )
                              right: <Id.Lit_DRightBracket ']]'>
                              redirects: []
                            )
                          terminator: <Id.Op_Semi _>
                        )
                      ]
                    )
                  then_kw: <Id.KW_Then then>
                  action: [
                    (command.Simple
                      blame_tok: <_Dbg_msg>
                      more_env: []
                      words: [
                        {<_Dbg_msg>}
                        {
                          (CommandSub
                            left_token: <Id.Left_DollarParen '$('>
                            child: 
                              (command.Simple
                                blame_tok: <tty>
                                more_env: []
                                words: [{<tty>}]
                                redirects: []
                                do_fork: T
                              )
                            right: <Id.Eof_RParen _>
                          )
                        }
                      ]
                      redirects: []
                      do_fork: T
                    )
                  ]
                  spids: [128 140]
                )
              ]
              else_kw: <Id.KW_Else else>
              else_action: [
                (command.Simple
                  blame_tok: <_Dbg_msg>
                  more_env: []
                  words: [{<_Dbg_msg>} {($ Id.VSub_DollarName _Dbg_tty)}]
                  redirects: []
                  do_fork: T
                )
              ]
              fi_kw: <Id.KW_Fi fi>
              redirects: []
            )
            (command.ControlFlow keyword:<Id.ControlFlow_Return return> arg_word:{<0>})
          ]
          redirects: []
          right: <Id.Lit_RBrace '}'>
        )
    )
  ]
)