CmdPeriod register objects to be cleared when Cmd-. is pressed

Superclass: Object

CmdPeriod allows you to register objects to perform an action when the user presses Cmd-. These objects must implement a method called -cmdPeriod which performs the necessary tasks. (You can add such a method in your custom classes.) Note that since [Function] implements -cmdPeriod as a synonym for -value, it is possible to register any function (and thus any arbitrary code) for evaluation when Cmd-. is pressed.

N.B. Cmd-. uses an [IdentitySet] to store its registered objects. For this reason you cannot rely on the order in which the objects will be cleared. If you need -cmdPeriod to be called on a set of objects in a given order then it is best to wrap those within a [Function] and register that. (See example below.)

Class Methods

*add(object)

Registers an object to be cleared when Cmd-. is pressed. This object will stay registered until it is explicitly removed, and will thus respond to additional presses of Cmd-.

*remove(object)

Removes an object that was previously registered.

*doOnce(object)

Registers an Object o be evaluated once, and then unregistered.

Examples

(

f = {"foo".postln };

g = {"bar".postln };

CmdPeriod.add(f);

CmdPeriod.add(g);

)

// Now press Cmd-.

CmdPeriod.remove(g);

// Now press Cmd-. Only f executes

CmdPeriod.remove(f); // must explicitly cleanup

//// Controlling order of execution

(

f = {"first".postln };

g = {"second".postln };

// order is arbitrary, so wrap in a function

h = { f.cmdPeriod; g.cmdPeriod;};

CmdPeriod.add(h);

)

// Now press Cmd-.

CmdPeriod.remove(h);

// note that often you want to automatically remove the function once it is evaluated

// instead of

f = { "foo".postln; CmdPeriod.remove(f) };

CmdPeriod.add(f);

// you can write:

CmdPeriod.doOnce { "foo".postln }

// a typical example:

(

w = SCWindow.new("close on cmd-.").front;

CmdPeriod.doOnce { w.close };

)