Ptg[] ptg = HSSFFormulaParser.parse("myFunc()", w);
// myFunc() actually takes 1 parameter. Don't know if POI will ever be able to detect this problem
// the name gets encoded as the first arg
NamePtg tname = (NamePtg) ptg[0];
assertEquals("myFunc", tname.toFormulaString(book));
AbstractFunctionPtg tfunc = (AbstractFunctionPtg) ptg[1];
assertTrue(tfunc.isExternalFunction());
}