Q works incorrect with mixin variable declaration inside a lambda.
If you try to assign a global variable with the same name after local declaration, like:
{ myVar:10; myVar::20 }
In this case global double colons are treated as local assignment that could case an error.
In opposite way, when first declare a variable as global one and try to assign local value, like:
{myVar::10; myVar:20}
an error will be thrown.