(CommandList
  children: [
    (C {(set)} {(-e)})
    (C {(cd)} 
      {
        (CommandSubPart
          command_list: 
            (CommandList
              children: [
                (C {(dirname)} 
                  {
                    (DQ 
                      (BracedVarSub
                        token: <VSub_Name BASH_SOURCE>
                        bracket_op: (ArrayIndex expr:(ArithWord w:{(Lit_Digits 0)}))
                        spids: [17 22]
                      )
                    )
                  }
                )
              ]
            )
          left_token: <Left_CommandSub "$(">
          spids: [12 25]
        ) (/..)
      }
    )
    (C {(echo)} {(DQ ("*** Patching SDK"))})
    (C {(dart)} {(-c)} {(tool/patch_sdk.dart)} {(tool/input_sdk)} {(gen/patched_sdk)})
    (C {(echo)} {(DQ ("*** Compiling SDK to JavaScript"))})
    (SimpleCommand
      words: [
        {(dart)}
        {(-c)}
        {(tool/build_sdk.dart)}
        {(--dart-sdk)}
        {(gen/patched_sdk)}
        {(--dart-sdk-summary) (Lit_Other "=") (build)}
        {(--summary-out)}
        {(lib/sdk/ddc_sdk.sum)}
        {(--modules) (Lit_Other "=") (amd)}
        {(-o)}
        {(lib/js/amd/dart_sdk.js)}
        {(--modules) (Lit_Other "=") (es6)}
        {(-o)}
        {(lib/js/es6/dart_sdk.js)}
        {(--modules) (Lit_Other "=") (common)}
        {(-o)}
        {(lib/js/common/dart_sdk.js)}
        {(--modules) (Lit_Other "=") (legacy)}
        {(-o)}
        {(lib/js/legacy/dart_sdk.js)}
        {(DQ ($ VSub_At "$@"))}
      ]
      redirects: [
        (Redir op_id:Redir_Great fd:-1 arg_word:{(tool/sdk_expected_errors.txt)} spids:[134])
      ]
    )
  ]
)