I have an unordered_map of functions that should be called on an object when an XML file is parsed.
I have found that boost::function has a base class named boost::function_base, however as expected I cannot invoke it because I don't have the signuture of the function.
Since all of those functions are setter functions, I can guarantee that they return void and have only one parameter of an unknown type.
Is there any better way to resolve the type other then an if-else-if branch which I am trying to avoid?
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Use a boost::variant is the best way to go. How could you possibly invoke a function with an unknown parameter type, anyway?
Puppy
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+1 i second that. A variant knows what type is stored, so he can avoid the if-else-if branch. – Johannes Schaub - litb Sep 12 '10 at 20:17
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@Johannes Schaub - litb: But then how can I just call the function? I still need to know the type I am resolving. – the_drow Sep 12 '10 at 21:57
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@the_drow look into visitation. boost.variant manual has information on it. – Johannes Schaub - litb Sep 12 '10 at 22:10
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@Johannes Schaub - litb: So I still need to specify the signuture of my functions, right? – the_drow Sep 13 '10 at 07:41
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boost::function is designed for compile time polymorphism only. Why don't you just use a regular function pointer? I.e.
typedef void (*function_type)(void *);
Billy ONeal
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