def scalar_symbols(exprs):
 new_names = (('_%d' % i) for i in itertools.count(1))
 scalars = []
 names = set()
 for expr in exprs:
  if (expr._name and (expr._name not in names)):
   name = expr._name
   names.add(name)
  else:
   name = next(new_names)
  s = symbol(name, expr.schema)
  scalars.append(s)
 return scalars

def scalar_symbols ( exprs ) : new_names = ( ( '_%d' % i ) for i in itertools . count ( 1 ) ) scalars = [ ] names = set ( ) for expr in exprs : if ( expr . _name and ( expr . _name not in names ) ) : name = expr . _name names . add ( name ) else : name = next ( new_names ) s = symbol ( name , expr . schema ) scalars . append ( s ) return scalars
gives a sequence of scalar symbols to mirror these expressions examples .