Make DB::Pool accept a block

src/db/database.cr

@@ -29,7 +29,7 @@ module DB
       pool_options = @driver.connection_pool_options(params)
 
       @pool = uninitialized Pool(Connection) # in order to use self in the factory proc
-      @pool = Pool.new(->{ @driver.build_connection(self).as(Connection) }, **pool_options)
+      @pool = Pool.new(**pool_options) { @driver.build_connection(self).as(Connection) }
     end
 
     # Closes all connection to the database.

src/db/pool.cr

@@ -7,7 +7,7 @@ module DB
     @total = [] of T
     @checkout_timeout : Float64
 
-    def initialize(@factory : Proc(T), @initial_pool_size = 1, @max_pool_size = 1, @max_idle_pool_size = 1, @checkout_timeout = 5.0)
+    def initialize(@initial_pool_size = 1, @max_pool_size = 1, @max_idle_pool_size = 1, @checkout_timeout = 5.0, &@factory : -> T)
       @initial_pool_size.times { build_resource }
 
       @availability_channel = Channel(Nil).new