A case or a shift character is only stored if it is not implied by the current case or shift and the
next character. Examples may make this clear (here it is assumed that space occurs in both sets but shift
characters only on inner set).
Paper tape (7-hole) Store
A lower-case a A shift-out a
A space lower-case a A space shift-out a
A lower-case space a A shift-out lower-case space
A upper-case A A shift-out upper-case shift-in A
In the third example the lower-case character must be stored because the space character occurs in both sets,
so that the lower-case is not implied by it.
This convention would require that no case or shift character were finally stored until the next input
character had been recognised, but enables an exact copy to be output of a tape which has been input.