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Subject: Re: [boost] Re : BOOST_FOREACH like macro for map
From: Stewart, Robert (Robert.Stewart_at_[hidden])
Date: 2009-10-21 08:44:37

Steven Watanabe wrote:
> Stewart, Robert wrote:
> >
> > template <class T, class U>
> > U const &
> > get_value(std::map<T,U> const & _map, T const & _key)
> > {
> > typename std::map<T,U>::const_iterator it(_map.find(_key));
> > if (it != _map.end())
> > {
> > return it->second;
> > }
> > throw std::domain_error("key not found");
> > }
> Wouldn't it be better to return a null pointer instead of throwing an
> exception?

The original use case was written assuming the element was found. To satisfy that, you need to return a reference and throw an exception. If the OP is happy with testing a pointer, I agree with you.

Rob Stewart robert.stewart_at_[hidden]
Software Engineer, Core Software using std::disclaimer;
Susquehanna International Group, LLP

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