It appears that LLVM has quite a number of dyn_casts (which I find quite
natural) The suggested idiom:
if (ConstantExpr* ce = dyn_cast<ConstantExpr>(*j)) {
}
is fine, and IIRC even used in TC++PL, but it occured to me that we can do
even better:
if (dyn_caster<ConstantExpr> ce = *j) {
}
where dyn_caster is defined like this:
template<class T>
class dyn_caster
{
public:
template<class T2>
dyn_caster(T2& t)
: m_ptr(dyn_cast<T>(t))
{}
T& operator*() const { return *m_ptr; }
T* operator->() const { return m_ptr; }
operator void*() const { return m_ptr; }
private:
T* m_ptr;
};
This allows to type the type name only once, not twice. I'm not sure if this
good idea yet, but though I'd just throw it in, in case anybody will be
interested.
- Volodya
On Thu, 17 Jun 2004, Vladimir Prus wrote:> This allows to type the type name only once, not twice. I'm not sure if this > good idea yet, but though I'd just throw it in, in case anybody will be > interested.That is definitely interesting and would reduce some clutter. I need to think about this a bit. I don't really like the name dyn_caster, maybe dyn_casted? I'm not sure. :) The nice thing about the dyn_cast way of doing things is that it IS an idiom that people are used to. Hrm, -Chris -- http://llvm.cs.uiuc.edu/ http://www.nondot.org/~sabre/Projects/