Sometimes you will like to superpose two items at the same point of the pattern underlying your diagram, like in the following example: A B C D The command for superposing two items is +12+ where 1 and 2 stand for the two items; the two arguments 1 and 2 are automatically processed in Math mode. The previous diagram can thus be typed as
\DIAG {A} \n {\ear} \n {B} \nn {\nar} \n {\cross{\near}{\sear}} \n {\sar} \nn {C} \n {\ear} \n {D} \diag
When superposing two arrows, the ++ command can have the undesired effect that one of the arrows will bump into the name of the other arrow. A special command has been designed to correct such a defect and is explained in section 17. For that reason, the ``cross'' option could be considered as a special feature of the Diagram Macros: one which requires your help.