print "'$_'" for split '([&/+-])|\s+', '129-129A & B-131 NORTH AV';

'129'                   ## Matches the first '-', produces '129' 
'-'                     ## and the captured delimiter
'129A'                  ## Match the first space, return '129A' 
Use of uninit...        ## and an undef for the empty capture
''                      ## and a nullstring?
''                      ## Match the '&', produces another null string?
'&'                     ## and the captured delimiter
''
Use of uninit...        ## Match the seecomd space, produce an undef 
''                      ## and a null string?
'B'                     ## Match the second '-', produce the 'B'
'-'                     ## And the captured delimiter
'131'                   ## Match the 3rd space, produce '131'
Use of uninit...        ## and undef for the empty capture
''                      ## and a null string?
'NORTH'                 ## Match the fourth space, produce 'NORTH'
Use of uninit...        ## and undef for the empty capture
''                      ## and a null string for luck?
'AV'                    ## And the tail of the string.