private void parseConstructionDeclaration() throws XPathException {
        if (foundConstructionDeclaration) {
            grumble("declare construction appears more than once", "XQST0067");
        }
        foundConstructionDeclaration = true;
        nextToken();
        expect(Token.NAME);
        int val;
        if ("preserve".equals(t.currentTokenValue)) {
            val = Validation.PRESERVE;
//            if (!env.getExecutable().isSchemaAware()) {
//                grumble("construction mode preserve is allowed only with a schema-aware query");
//            }
        } else if ("strip".equals(t.currentTokenValue)) {
            val = Validation.STRIP;
        } else {
            grumble("construction mode must be 'preserve' or 'strip'");
            val = Validation.STRIP;
        }
        ((QueryModule)env).setConstructionMode(val);
        nextToken();
    }