Strange error happens only with -inline flag

[finalpatch]

The following code compiles fine with the command "dmd test.d"

import std.array, std.algorithm, std.algorithm, std.string;
void main()
{
	int[string] s;
	auto a = join(map!(a=>format("%s %d", a, s[a]))(s.keys));
}

However, if I try to compile it with "dmd -inline test.d", I get 
this error message:

test.d(5): Error: function D main is a nested function and cannot 
be accessed from std.array.join!(MapResult!(__lambda2, 
string[])).join

Isn't -inline supposed to be completely transparent?