VMS Help MMS, Description File, Predefined functions, Text operations, PATSUBST  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    $(PATSUBST pattern...,to,text)

    Pattern substitution. Each word in 'text' that matches any
    'pattern'    word is replaced by 'to'. 'pattern' words may contain
    the wildcard characters * and %. If 'to' also contains wildcard
    characters, they will be replaced by the text that matched the
    wildcard characters in 'pattern'.