(command.CommandList
  children: [
    (C {<_Dbg_help_add>} {<trace>} 
      {
        (SQ <'**trace** *function*\n'> <'\n'> <'trace alias *alias*\n'> <'\n'> 
          <'Set "xtrace" (set -x) tracing when *function is called.\n'> <'\n'> <'See also "untrace" and "debug".'>
        )
      }
    )
    (command.ShFunction
      name: _Dbg_do_trace
      body: 
        (BraceGroup
          children: [
            (command.If
              arms: [
                (if_arm
                  cond: 
                    (condition.Shell
                      commands: [
                        (command.Sentence
                          child: 
                            (command.DParen
                              child: 
                                (arith_expr.Binary
                                  op_id: Id.Arith_DEqual
                                  left: {($ Id.VSub_Pound '$#')}
                                  right: {<Id.Lit_Digits 0>}
                                )
                            )
                          terminator: <Id.Op_Semi _>
                        )
                      ]
                    )
                  action: [
                    (C {<_Dbg_errmsg>} {(DQ <'trace: missing function name.'>)})
                    (command.ControlFlow
                      token: <Id.ControlFlow_Return return>
                      arg_word: {<2>}
                    )
                  ]
                  spids: [96 109]
                )
              ]
            )
            (C {<typeset>} {<-r>} {<Id.Lit_VarLike 'fn='> ($ Id.VSub_Number '$1')})
            (C {<typeset>} {<-ri>} 
              {<Id.Lit_VarLike 'clear_debug_trap='> 
                (braced_var_sub
                  token: <Id.VSub_Number 2>
                  suffix_op: (suffix_op.Unary tok:<Id.VTest_ColonHyphen ':-'> arg_word:{<1>})
                )
              }
            )
            (command.AndOr
              ops: [Id.Op_DPipe]
              children: [
                (C {<_Dbg_is_function>} {(DQ ($ Id.VSub_DollarName '$fn'))} 
                  {($ Id.VSub_DollarName '$_Dbg_set_debug')}
                )
                (BraceGroup
                  children: [
                    (C {<_Dbg_errmsg>} 
                      {
                        (DQ <'trace: function '> 
                          (word_part.EscapedLiteral
                            token: <Id.Lit_EscapedChar '\\"'>
                          ) ($ Id.VSub_DollarName '$fn') (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) 
                          <' is not a function.'>
                        )
                      }
                    )
                    (command.ControlFlow
                      token: <Id.ControlFlow_Return return>
                      arg_word: {<3>}
                    )
                  ]
                )
              ]
            )
            (command.AndOr
              ops: [Id.Op_DPipe]
              children: [
                (command.ShAssignment
                  pairs: [
                    (assign_pair
                      lhs: (sh_lhs_expr.Name name:cmd)
                      op: assign_op.Equal
                      rhs: 
                        {
                          (command_sub
                            left_token: <Id.Left_DollarParen '$('>
                            child: (C {<typeset>} {<-f>} {<-->} {(DQ ($ Id.VSub_DollarName '$fn'))})
                          )
                        }
                      spids: [179]
                    )
                  ]
                )
                (BraceGroup
                  children: [
                    (C {<_Dbg_errmsg>} 
                      {
                        (DQ <'Can\'t find function definition for definition '> 
                          (word_part.EscapedLiteral
                            token: <Id.Lit_EscapedChar '\\"'>
                          ) ($ Id.VSub_DollarName '$fn') (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) <.>
                        )
                      }
                    )
                    (command.ControlFlow
                      token: <Id.ControlFlow_Return return>
                      arg_word: {<4>}
                    )
                  ]
                )
              ]
            )
            (command.If
              arms: [
                (if_arm
                  cond: 
                    (condition.Shell
                      commands: [
                        (command.Sentence
                          child: 
                            (command.DBracket
                              expr: 
                                (bool_expr.Binary
                                  op_id: Id.BoolBinary_EqualTilde
                                  left: {($ Id.VSub_DollarName '$cmd')}
                                  right: {(SQ <'^function '>)}
                                )
                            )
                          terminator: <Id.Op_Semi _>
                        )
                      ]
                    )
                  action: [
                    (command.ShAssignment
                      pairs: [
                        (assign_pair
                          lhs: (sh_lhs_expr.Name name:cmd)
                          op: assign_op.Equal
                          rhs: 
                            {
                              (DQ <'function old_'> 
                                (braced_var_sub
                                  token: <Id.VSub_Name cmd>
                                  suffix_op: (suffix_op.Slice begin:{<Id.Lit_Digits 9>})
                                )
                              )
                            }
                          spids: [235]
                        )
                      ]
                    )
                  ]
                  spids: [216 232]
                )
              ]
              else_action: [
                (command.ShAssignment
                  pairs: [
                    (assign_pair
                      lhs: (sh_lhs_expr.Name name:cmd)
                      op: assign_op.Equal
                      rhs: {(DQ <old_> (${ Id.VSub_Name cmd))}
                      spids: [249]
                    )
                  ]
                )
              ]
            )
            (command.AndOr
              ops: [Id.Op_DAmp]
              children: [
                (command.DParen child:<Id.Lit_ArithVarLike _Dbg_set_debug>)
                (C {<echo>} {(DQ ($ Id.VSub_DollarName '$cmd'))})
              ]
            )
            (C {<typeset>} {<Id.Lit_VarLike 'save_clear_debug_trap_cmd='> (SQ )})
            (C {<typeset>} {<Id.Lit_VarLike 'restore_trap_cmd='> (SQ )})
            (command.If
              arms: [
                (if_arm
                  cond: 
                    (condition.Shell
                      commands: [
                        (command.Sentence
                          child: (command.DParen child:<Id.Lit_ArithVarLike clear_debug_trap>)
                          terminator: <Id.Op_Semi _>
                        )
                      ]
                    )
                  action: [
                    (command.ShAssignment
                      pairs: [
                        (assign_pair
                          lhs: (sh_lhs_expr.Name name:save_clear_trap_cmd)
                          op: assign_op.Equal
                          rhs: {(SQ <'local old_handler=$(trap -p DEBUG); trap - DEBUG'>)}
                          spids: [303]
                        )
                      ]
                    )
                    (command.ShAssignment
                      pairs: [
                        (assign_pair
                          lhs: (sh_lhs_expr.Name name:restore_trap_cmd)
                          op: assign_op.Equal
                          rhs: {(SQ <'eval $old_handler'>)}
                          spids: [309]
                        )
                      ]
                    )
                  ]
                  spids: [289 300]
                )
              ]
            )
            (command.AndOr
              ops: [Id.Op_DPipe]
              children: [
                (C {<eval>} {(DQ ($ Id.VSub_DollarName '$cmd'))})
                (BraceGroup
                  children: [
                    (C {<_Dbg_errmsg>} 
                      {
                        (DQ <'Error in renaming function '> 
                          (word_part.EscapedLiteral
                            token: <Id.Lit_EscapedChar '\\"'>
                          ) ($ Id.VSub_DollarName '$fn') (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) <' to '> 
                          (word_part.EscapedLiteral
                            token: <Id.Lit_EscapedChar '\\"'>
                          ) <old_> (${ Id.VSub_Name fn) (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) <.>
                        )
                      }
                    )
                    (command.ControlFlow
                      token: <Id.ControlFlow_Return return>
                      arg_word: {<5>}
                    )
                  ]
                )
              ]
            )
            (command.ShAssignment
              pairs: [
                (assign_pair
                  lhs: (sh_lhs_expr.Name name:cmd)
                  op: assign_op.Equal
                  rhs: 
                    {
                      (DQ (${ Id.VSub_Name fn) <'() {\n'> <'    '> 
                        ($ Id.VSub_DollarName '$save_clear_trap_cmd') <'\n'> <'    typeset -ri old_set_x=is_traced\n'> <'    set -x\n'> <'    old_'> 
                        ($ Id.VSub_DollarName '$fn') <' '> (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) 
                        (word_part.EscapedLiteral
                          token: <Id.Lit_EscapedChar '\\$'>
                        ) <'@'> (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) <'\n'> <'    typeset -ri rc='> 
                        (word_part.EscapedLiteral
                          token: <Id.Lit_EscapedChar '\\$'>
                        ) <'?\n'> <'    (( old_set_x == 0 )) && set +x # still messes up of fn did: set -x\n'> <'    '> 
                        ($ Id.VSub_DollarName '$restore_trap_cmd') <'\n'> <'    return '> (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\$'>) <'rc\n'> <'    }\n'>
                      )
                    }
                  spids: [355]
                )
              ]
            )
            (command.AndOr
              ops: [Id.Op_DAmp]
              children: [
                (command.DParen child:<Id.Lit_ArithVarLike _Dbg_set_debug>)
                (C {<echo>} {(DQ ($ Id.VSub_DollarName '$cmd'))})
              ]
            )
            (command.AndOr
              ops: [Id.Op_DPipe]
              children: [
                (C {<eval>} {(DQ ($ Id.VSub_DollarName '$cmd'))})
                (command.ControlFlow
                  token: <Id.ControlFlow_Return return>
                  arg_word: {<6>}
                )
              ]
            )
            (C {<_Dbg_msg>} 
              {
                (DQ (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) 
                  ($ Id.VSub_DollarName '$fn') (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) <' renamed '> 
                  (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) <old_> (${ Id.VSub_Name fn) (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) 
                  <' and traced by '> (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) (${ Id.VSub_Name fn) 
                  (word_part.EscapedLiteral token:<Id.Lit_EscapedChar '\\"'>) <.>
                )
              }
            )
            (command.ControlFlow token:<Id.ControlFlow_Return return> arg_word:{<0>})
          ]
        )
    )
  ]
)