boost/lambda and structures

[Rafal Dabrowa]

Suppose I have the following structure:

struct xy { int x, y; };

and the following vector:

vector<xy> v(10);

I want to use boost/lambda for find an item in the table.
Let's say, with x member value equal to 10. I wrote
something like this:

vector<xy>::iterator pos = find_if(v.begin(), v.end(), _1.x == 10);

but this doesn't work. Compiler complains that 'const struct
boost::lambda::lambda_functor<boost::lambda:laceholder<1> >' has no
member named 'x'.
How the above code should look correctly ?


Rafal

 

[Rapscallion]

This is a C++, not a Boost group.

 

[Jeff Flinn]

Suppose I have the following structure:

struct xy { int x, y; };

and the following vector:

vector<xy> v(10);

I want to use boost/lambda for find an item in the table.
Let's say, with x member value equal to 10. I wrote
something like this:

vector<xy>::iterator pos = find_if(v.begin(), v.end(), _1.x ==
10);
but this doesn't work. Compiler complains that 'const struct
boost::lambda::lambda_functor<boost::lambda:laceholder<1> >' has no
member named 'x'.
How the above code should look correctly ?

You might want to join the boost user mailing list where your're more apt to
get more expert help. See www.boost.org. In the meantime, you may have to
use:

bind( &xy::x, _1 ) == 10

This should work. I'm not sure if there's a non-bind syntax that would work.

Jeff Flinn

 

[Rafal Dabrowa]

You might want to join the boost user mailing list where your're more apt to
get more expert help. See www.boost.org. In the meantime, you may have to
use:

bind( &xy::x, _1 ) == 10

This should work. I'm not sure if there's a non-bind syntax that would work.

Thank you.


Rafal