(command.CommandList
  children: [
    (command.ShFunction
      name: printHelp
      body: 
        (BraceGroup
          children: [
            (C {<echo>} 
              {(DQ <'Usage: '> ($ Id.VSub_Number '$0') <' -f find -r replace FILES_TO_RENAME*'>)}
            )
            (C {<echo>} {<-e>} {(DQ <Id.Lit_BadBackslash '\\'> <'t-f The text to find in the filename'>)})
            (C {<echo>} {<-e>} 
              {(DQ <Id.Lit_BadBackslash '\\'> <'t-r The text used to replace with in the filename'>)}
            )
            (command.ControlFlow token:<Id.ControlFlow_Exit exit> arg_word:{<1>})
          ]
        )
    )
    (command.WhileUntil
      keyword: <Id.KW_While while>
      cond: 
        (condition.Shell
          commands: [
            (command.Sentence
              child: (C {<getopts>} {(DQ <'f:r:'>)} {<opt>})
              terminator: <Id.Op_Semi _>
            )
          ]
        )
      body: 
        (command.DoGroup
          children: [
            (command.Case
              to_match: {(DQ ($ Id.VSub_DollarName '$opt'))}
              arms: [
                (case_arm
                  pat_list: [{<r>}]
                  action: [
                    (command.ShAssignment
                      pairs: [
                        (assign_pair
                          lhs: (sh_lhs_expr.Name name:replace)
                          op: assign_op.Equal
                          rhs: {(DQ ($ Id.VSub_DollarName '$OPTARG'))}
                          spids: [75]
                        )
                      ]
                    )
                  ]
                  spids: [71 73 80 -1]
                )
                (case_arm
                  pat_list: [{<f>}]
                  action: [
                    (command.ShAssignment
                      pairs: [
                        (assign_pair
                          lhs: (sh_lhs_expr.Name name:fnd)
                          op: assign_op.Equal
                          rhs: {(DQ ($ Id.VSub_DollarName '$OPTARG'))}
                          spids: [87]
                        )
                      ]
                    )
                  ]
                  spids: [83 85 92 -1]
                )
                (case_arm
                  pat_list: [{<Id.Lit_QMark '?'>}]
                  action: [(C {<printHelp>})]
                  spids: [95 97 101 -1]
                )
              ]
            )
          ]
        )
    )
    (C {<shift>} 
      {
        (word_part.ArithSub
          anode: 
            (arith_expr.Binary
              op_id: Id.Arith_Minus
              left: {($ Id.VSub_DollarName '$OPTIND')}
              right: {<Id.Lit_Digits 1>}
            )
        )
      }
    )
    (command.If
      arms: [
        (if_arm
          cond: 
            (condition.Shell
              commands: [
                (command.AndOr
                  ops: [Id.Op_DPipe]
                  children: [
                    (C {<Id.Lit_LBracket '['>} {<-z>} {($ Id.VSub_DollarName '$replace')} 
                      {<Id.Lit_RBracket ']'>}
                    )
                    (C {<Id.Lit_LBracket '['>} {<-z>} {($ Id.VSub_DollarName '$fnd')} 
                      {<Id.Lit_RBracket ']'>}
                    )
                  ]
                )
              ]
            )
          action: [
            (command.Sentence
              child: (C {<echo>} {(DQ <'Need a string to find and a string to replace'>)})
              terminator: <Id.Op_Semi _>
            )
            (C {<printHelp>})
          ]
          spids: [123 143]
        )
      ]
    )
    (command.ForEach
      iter_name: i
      iter_words: [{($ Id.VSub_At '$@')}]
      do_arg_iter: F
      body: 
        (command.DoGroup
          children: [
            (command.ShAssignment
              pairs: [
                (assign_pair
                  lhs: (sh_lhs_expr.Name name:newname)
                  op: assign_op.Equal
                  rhs: 
                    {
                      (command_sub
                        left_token: <Id.Left_DollarParen '$('>
                        child: 
                          (command.Pipeline
                            children: [
                              (C {<echo>} {($ Id.VSub_DollarName '$i')})
                              (C {<sed>} 
                                {
                                  (DQ <'s/'> ($ Id.VSub_DollarName '$fnd') <'/'> 
                                    ($ Id.VSub_DollarName '$replace') <'/'>
                                  )
                                }
                              )
                            ]
                            negated: F
                          )
                      )
                    }
                  spids: [170]
                )
              ]
            )
            (C {<mv>} {($ Id.VSub_DollarName '$i')} {($ Id.VSub_DollarName '$newname')})
            (C {<echo>} 
              {
                (DQ <'Renamed file '> ($ Id.VSub_DollarName '$i') <' to '> 
                  ($ Id.VSub_DollarName '$newname')
                )
              }
            )
          ]
        )
    )
  ]
)