Re: [Boost-users] boost bind question, can it create a functor with more arguments than needed

gast 128 wrote:

Dear all,

Probably this is something one does not encounter often, but I have here an interface which expects more arguments than needed, e.g.:

void SomeInterface(boost::function<void (Arg1, Arg2)> fcCallback) {}

now I have another functor like: boost::function<void (Arg1)> fc;

I want fc apply to SomeInterface, and it only needs to fill in argument1. So I need something like boost::bind(fc, _1, _2) to get it compilable for SomeInterface, only bind now thinks that fc has a prototype of two arguments. Is there a way to tell bind to ignore argument2 (without explicit write a functor)?

Yes there is, just tell it so: bind(fc, _1) is as close to "I want fc apply to SomeInterface, and it only needs to fill in argument1" as it can get. ;-) You can also use bind(fc, _2) if you want to pass Arg2 to fc and ignore Arg1.