Portability | non-portable (requires concurrency) |
---|---|
Stability | provisional |
Maintainer | libraries@haskell.org |
The Draw
monad, with graphical objects as a special case.
Documentation
:: Draw a | a pre-operation, whose value is passed to the other two components. |
-> (a -> Draw b) | a post-operation, to be performed on exit from the bracket, whether normal or by an exception. |
-> (a -> Draw c) | the drawing action inside the bracket. |
-> Draw c |
Wrap a drawing action in initialization and finalization actions.
:: Draw a | a pre-operation, whose value is passed to the other two components. |
-> (a -> Draw b) | a post-operation, to be performed on exit from the bracket, whether normal or by an exception. |
-> Draw c | the drawing action inside the bracket. |
-> Draw c |
A variant of bracket
in which the inner drawing action does not
use the result of the pre-operation.