New to VS 2012 and Lambada programming

[maverick786us]

I am new to VC++ 2012 and Lambada programming. I want use a local initialized varaible withint he Lambada code block.

int _tmain(int argc, _TCHAR* argv[])
{
uri_builder uri(L"http://*:2001/");
	http_listener listener(uri.to_uri());
	utility::string_t strPost = L"";

-------------------------------------------------------------------------------------------------------------------------------
-------------------------------------------------------------------------------------------------------------------------------
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listener.support(methods::POST,[](http_request req)
	{
		std::cout << "Serving POST" << std::endl;
		req.extract_string(true).then([req](utility::string_t body)
		{
			std::wcout << body << std::endl;
			strPost = body;
		});
	});	
}

In this section the compiler throws this error

Error	3	error C3493: 'strPost' cannot be implicitly captured because no default capture mode has been specified

How can I overcome this problem, how can I use it across the whole function?

[OReubens]

Ah yes, lambada programming.
Where you kill bugs with your awesome sexy dance moves. :-)

1) it's lambda (from the greek letter 'lambda')
better get this right before people make fun of you.
oh dear too late ;-)

2)
you're using strPost, but you have not mentioned strPost in the capture clause, nor have you specified a default capture mode (by value or by reference) for variables.
so you get an error.

since you're changing it, you probably want to capture by reference . IN that case add &strPost to the capture clauses (or add & to capture anything other than req by reference).

[maverick786us]

Ah yes, lambada programming.
Where you kill bugs with your awesome sexy dance moves. :-)

1) it's lambda (from the greek letter 'lambda')
better get this right before people make fun of you.
oh dear too late ;-)

2)
you're using strPost, but you have not mentioned strPost in the capture clause, nor have you specified a default capture mode (by value or by reference) for variables.
so you get an error.

since you're changing it, you probably want to capture by reference . IN that case add &strPost to the capture clauses (or add & to capture anything other than req by reference).

Sorry, if I didn't explain well in the original post. I want a local variable to be access across various lambda code blocks.

[ovidiucucu]

Let’s Write a “Hello Lambda!”
It's intentionally made enough stupid, in order to explain lambdas at beginners level.

[ovidiucucu]

[...] I want a local variable to be access across various lambda code blocks.

Beware! In your case the lambda call is asynchronous, so it's not OK to capture local variables by reference.