dmd 2.068 deducing purity

[Jack Applegame via Digitalmars-d-learn]

Using lambdas in 2.068 becomes painful:

import std.algorithm;
struct Foo {
        int baz(int v) {
                static int id;
                return v + id++;
        }
        void bar() {
                auto arr1 = [1, 2, 3];
                auto arr2 = [4, 5, 6];
                arr1.map!(i =>
                        arr2.map!(j => baz(i + j))
                );
        }
}

void main() {
}

Error: pure function 
'bug.Foo.bar.__lambda1!int.__lambda1.__lambda2' cannot call 
impure function 'bug.Foo.baz'

Also after switching to dmd 2.068 I got many stupid errors in 
lambdas (defined inside class non-static functions):

Error: need 'this' for '...' of type '...'

I have no idea how to fix it and had to go back to 2.067.