FUNCTION PARSALIAS()

  Short:
  ------
  PARSALIAS() Extracts the name of the alias from an expression

  Returns:
  --------
  <cAlias> => name of the alias

  Syntax:
  -------
  PARSALIAS(cExpress)

  Description:
  ------------
  Returns the ALIAS part of cExpress. If <cExpress> is
  not prefaced

  with an alias ( XXXX-> ) the current ALIAS() is
  returned.

  Examples:
  ---------
   cExpr := "CUSTOMER->LASTNAME"

   IF ISFIELD(cExpr)
     ?PARSALIAS(cExpr)  // displays CUSTOMER
     ?PARSFIELD(cExpr)  // displays LASTNAME
   ENDIF

  Warnings:
  ----------
  Does not verify if this is a valid field. Use
  ISFIELD().

  Source:
  -------
  S_FIELDS.PRG