question: public static void shiftMappingVector ( Vector mvec , int shift ) { for ( int i = 0 ; i < mvec . size ( ) ; i ++ ) { Vector line = ( Vector ) mvec . elementAt ( i ) ; for ( int j = 0 ; j < line . size ( ) ; j ++ ) { MappingObject mobj = ( MappingObject ) line . elementAt ( j ) ; if ( mobj . type == BEGIN_TLATOKEN ) { BeginTLAToken obj = ( BeginTLAToken ) mobj ; obj . setColumn ( obj . getColumn ( ) + shift ) ; } else if ( mobj . type == END_TLATOKEN ) { EndTLAToken obj = ( EndTLAToken ) mobj ; obj . setColumn ( obj . getColumn ( ) + shift ) ; } else if ( mobj . type == SOURCE_TOKEN ) { SourceToken obj = ( SourceToken ) mobj ; obj . setBeginColumn ( obj . getBeginColumn ( ) + shift ) ; obj . setEndColumn ( obj . getEndColumn ( ) + shift ) ; } } } }
target:  A mapping vector is a vector of vectors of MappingObject objects.  This transforms a mapping vector obtained from a TLAExpr object by a call of toMappingVector to produce the mapping vector that would have resulted from that call if the entire expression had been moved  to the right by `shift' characters.