# NOTE: This procedure creates a new interpreter, which may be "safe", and
  #       places a reference to it in a variable in the context of the caller
  #       identified by the varName argument.  The created interpreter has a
  #       fully functioning [package] command ensemble; all other commands do
  #       nothing and return nothing.  This procedure may raise script errors.
  #
  proc createInterp { varName } {
    #
    # NOTE: Prepare to provide the caller with the newly created interpreter
    #       reference.
    #
    upvar 1 $varName interp

    #
    # NOTE: Create a "safe" interpreter and set the global "dir" variable to
    #       a single period.  Generally, this is the only variable used by a
    #       package index file.  It should be noted that since [set] will be
    #       a NOP, attempts to use other variables in the specified package
    #       index file (e.g. ones [set] within it) will fail.
    #
    set interp [interp create -safe]
    interp eval $interp [list set dir .]

    #
    # NOTE: First, obtain the list of child namespaces to delete, if any, and
    #       then delete them all.  This should leave the global namespace and
    #       its commands / variables untouched.
    #
    set namespaces [interp eval $interp [list namespace children ::]]

    foreach namespace $namespaces {
      catch {
        interp eval $interp [list namespace delete $namespace]
      }
    }

    #
    # NOTE: Next, obtain the list of global commands and delete all of them
    #       except the [proc] and [package] commands.  The [proc] command is
    #       handled specially (last) and the [package] command is retained.
    #
    set commands [interp eval $interp [list info commands]]

    foreach command $commands {
      if {$command ne "proc" && $command ne "package"} then {
        interp eval $interp [list proc $command args ""]; # NOP
      }
    }

    if {![isEagle]} then {
      #
      # HACK: The "safe" interpreters in native Tcl do not contain
      #       the [file] command at all, not even for [file join]
      #       and [file split], which may be used in package index
      #       files; therefore, add it as a NOP command.
      #
      interp eval $interp [list proc file args ""]; # NOP
    }

    #
    # NOTE: Next, disable the [proc] command.  This must be done last
    #       because it is used to disable (i.e. via NOP) all the other
    #       global commands.
    #
    interp eval $interp [list proc proc args ""]; # NOP

    #
    # NOTE: Finally, return nothing as the created interpreter reference
    #       is placed directly into the variable specified by the caller.
    #
    return ""
  }

  #
  # NOTE: This procedure evaluates a script file and attempts to determine the
  #       list of new [package ifneeded] scripts added by it.  When successful
  #       it returns a list-of-lists.  Each element of the outer list contains