How to catch the exception in initialization list? [duplicate]
I have a question about how to catch the exception in the initialization list.
For example, we have a class Foo derived from Bar
class Foo {
public:
Foo(int i) {throw 0; }
}
class Bar : public Foo{
public:
Bar() : Foo(1) {}
}
I think the syntax is like this (even though it's better to catch such things in the caller. And what are you going to do once you caught it?)
Bar::Bar()
try
: Foo(1)
{
}
catch( const SomeException &e )
{
}
C++ has a mechanism for doing so, but it is rarely used. It is the function try block:
Bar::Bar()
try
: Foo(1)
{
}
catch( Something )
{
}
See this classic gotw, which outlines why it should only be used to translate exceptions (e.g., exception type FooException becomes BarException).
I believe this should be caught by the procedure creating the object.
Consider replacing the troublesome instance with a boost::optional
. Then you can defer its initialization into the body of the constructor.
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