Reverse application, i.e. x # f = f x. Useful for an object oriented style of programming.

(frame # frameSetTitle) "hi"

An Object a is a pointer to an object of type a. The a parameter is used to encode the inheritance relation. When the type parameter is unit (), it denotes an object of exactly that class, when the parameter is a type variable a, it specifies an object that is at least an instance of that class. For example in wxWidgets, we have the following class hierarchy:

EvtHandler
  |- Window
       |- Frame
       |- Control
           |- Button
           |- Radiobox

In wxHaskell, all the creation functions will return objects of exactly that class and use the () type:

frameCreate :: Window a -> ... -> IO (Frame ())
buttonCreate :: Window a -> ... -> IO (Button ())
...

In contrast, all the this (or self) pointers of methods can take objects of any instance of that class and have a type variable, for example:

windowSetClientSize :: Window a -> Size -> IO ()
controlSetLabel     :: Control a -> String -> IO ()
buttonSetDefault    :: Button a -> IO ()

This means that we can use windowSetClientSize on any window, including buttons and frames, but we can only use controlSetLabel on controls, not including frames.

In wxHaskell, this works since a Frame () is actually a type synonym for Window (CFrame ()) (where CFrame is an abstract data type). We can thus pass a value of type Frame () to anything that expects some Window a. For a button this works too, as it is a synonym for Control (CButton ()) which is in turn a synonym for Window (CControl (CButton ())). Note that we can't pass a frame to something that expects a value of type Control a. Of course, a Window a is actually a type synonym for EvtHandler (CWindow a). If you study the documentation in Graphics.UI.WX.Classes closely, you can discover where this chain ends :-).

Objects are not automatically deleted. Normally you can use a delete function like windowDelete to delete an object. However, almost all objects in the wxWidgets library are automatically deleted by the library. The only objects that should be used with care are resources as bitmaps, fonts and brushes.

A null object. Use with care.

Test for null object.

Cast an object to another type. Use with care.

Is this a managed object?

Delete a wxObject, works for managed and unmanaged objects.

Do something with the object pointer.

Extract the object pointer and raise an exception if NULL. Otherwise continue with the valid pointer.

Return an unmanaged object.

Create a managed object that will be deleted using |wxObject_SafeDelete|.

Finalize a managed object manually. (No effect on unmanaged objects.)

Remove the finalizer on a managed object. (No effect on unmanaged objects.)

Create an unmanaged object.

Create a managed object that will be deleted using |wxObject_SafeDelete|.

An Id is used to identify objects during event handling.

When creating a new window you may specify idAny to let wxWidgets assign an unused identifier to it automatically. Furthermore, it can be used in an event connection to handle events for any identifier.

Create a new unique identifier.

Bitwise or of two bit masks.

Unset certain bits in a bitmask.

Bitwise or of a list of bit masks.

(bitsSet mask i) tests if all bits in mask are also set in i.

Ignore the result of an IO action.

Properly release resources, even in the event of an exception.

Specialized variant of bracket where the return value is not required.

Run some computation afterwards, even if an exception occurs.

Run some computation afterwards, even if an exception occurs. Equals finally but with the arguments swapped.

Perform an action when a test succeeds.

A mutable variable. Use this instead of MVars or IORefs to accommodate for future expansions with possible concurrency.

Create a fresh mutable variable.

Get the value of a mutable variable.

Set the value of a mutable variable.

Update the value of a mutable variable and return the old value.

Swap the value of a mutable variable.

A Style is normally used as a flag mask to specify some window style

An EventId is identifies specific events.

Identifies tree items. Note: Replaces the TreeItemId object and takes automatically care of allocation issues.

Invalid tree item.

Is a tree item ok? (i.e. not invalid).

An abstract data type to define colors.

Create a color from a red/green/blue triple.

Create a color from a red/green/blue triple.

Returns a red color component

Returns a green color component

Returns a blue color component

Return an Int where the three least significant bytes contain the red, green, and blue component of a color.

Set the color according to an rgb integer. (see rgbIntFromColor).

Check of a color is valid (Colour::IsOk)

deprecated: use colorIsOk instead.

System Colors.

Convert a system color to a color.

A point has an x and y coordinate. Coordinates are normally relative to the upper-left corner of their view frame, where a positive x goes to the right and a positive y to the bottom of the view.

Construct a point.

Shorter function to construct a point.

Point at the origin.

A null point is not a legal point (x and y are -1) and can be used for some wxWidgets functions to select a default point.

A Size has a width and height.

Short function to construct a size

A null size is not a legal size (width and height are -1) and can be used for some wxWidgets functions to select a default size.

Returns True if the first size totally encloses the second argument.

The minimum of two sizes.

The maximum of two sizes.

A vector with an x and y delta.

Construct a vector.

Short function to construct a vector.

A zero vector

A null vector has a delta x and y of -1 and can be used for some wxWidgets functions to select a default vector.

A rectangle is defined by the left x coordinate, the top y coordinate, the width and the height.

Create a rectangle at a certain (upper-left) point with a certain size.

Construct a (positive) rectangle between two (arbitrary) points.

Create a rectangle of a certain size with the upper-left corner at (pt 0 0).

An empty rectangle at (0,0).

An null rectangle is not a valid rectangle (Rect -1 -1 -1 -1) but can used for some wxWidgets functions to select a default rectangle. (i.e. frameCreate).

Get the size of a rectangle.

A list with rectangles that constitute the difference between two rectangles.

The intersection between two rectangles.