/**
* Walks over an expression, and throws <code>CannotTranslate</code> if expression cannot be
* translated.
*
* @param rex Expression
* @throws org.eigenbase.oj.rel.JavaRelImplementor.TranslationTester.CannotTranslate if
* expression or a sub-expression cannot be translated
*/
protected void go(RexNode rex) throws CannotTranslate {
if (rex instanceof RexCall) {
final RexCall call = (RexCall) rex;
if (!translator.canConvertCall(call)) {
throw new CannotTranslate();
}
if (!deep) {
return;
}
RexNode[] operands = call.operands;
for (int i = 0; i < operands.length; i++) {
go(operands[i]);
}
} else if (rex instanceof RexFieldAccess) {
if (!deep) {
return;
}
go(((RexFieldAccess) rex).getReferenceExpr());
}
}
