GETUSER

Return the user field of a mapping

     USERFIELD = GETUSER(W,FIELD)

Input
W	Mapping
FIELD	Character string: name of structure field of USER field of W.

Output
USERFIELD	Requested field

  If FIELD is is the empty string ('') the entire user field is returned.

If the requested field does not exist USERFIELD = [];

Note the the USER field of mappings was originally intended for a user  defined description of mappings. Later its usage was extended to a field  for storing general information on mappings. For that reason 'old'  mappings without a structure in the user field are transformed such that  this information is stored in a subfield USER in the user field. It can  be retrieved by GETUSER(W).