Copies &closure into a new closure. The new closure environment is initialized with all of the specified key/value pair arguments.
&closure - the closure to copy into a new instance.
$key => value - sets $key in the this scope of the new closure to the right hand side value.!!this -
... - any number of $key => value pairs may be specified.
A new closure.
$myfunc = lambda({ println("foo! $x"); $x++; }, $x => 0); [$myfunc]; [$myfunc];
foo! 0 foo! 1