code: private Term evalIsNumeric(Function term) {
  		Term innerTerm = term.getTerm(0);
  		if (innerTerm instanceof Function) {
  			Function function = (Function) innerTerm;
  			return termFactory.getBooleanConstant(function.isDataTypeFunction() && isNumeric(function.getFunctionSymbol()));
  		}
  		else {
  			return term;
  		}
  	}
docs: /*
  Expression evaluator for isNumeric() function