root/lu/LUTimer.lua

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-- Title:               LUTimer.lua
-- Description:         Like a square peg in a round hole
-- Author:              Raphaël Szwarc http://alt.textdrive.com/lua/
-- Creation Date:       February 1, 2005
-- Legal:               Copyright (C) 2005 Raphaël Szwarc
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-- import dependencies
local LUObject = require( "LUObject" )
local LUTask = require( "LUTask" )
local os = require( "os" )

-- define the class
local super = LUObject
local self = super()

-- initialization method
function self:init( aTarget, anInterval, shouldRepeat )
        self = super.init( self )

        self._target = aTarget
        self._interval = anInterval
        self._shouldRepeat = shouldRepeat
        
        return self
end        

-- method to access the timer interval
function self:interval()
        return self._interval
end

 -- method to access the timer target
function self:target()
        return self._target
end

 -- method to access the shouldRepeat variable
function self:shouldRepeat()
        if self._shouldRepeat == nil then
                self._shouldRepeat = false
        end

        return self._shouldRepeat
end

 -- method to stop this timer
function self:stop()
        self._shouldRepeat = false

        return self
end

 -- method to access the clock
function self:clock()
        if self._clock == nil then
                self._clock = os.clock()
        end
        
        return self._clock
end

 -- method to reset the clock
function self:resetClock()
        self._clock = nil
end

-- method to start this reader task
function self:start()
        if self._task == nil then
                self:task():run()
        end
        
        return self
end

-- method to access this reader task
function self:task()
        if self._task == nil then
                self._task = LUTask( self )
        end
        
        return self._task
end

 -- method to run the timer
function self:run()
        repeat
                if ( os.clock() - self:clock() ) >= self:interval() then
                        self:target():run( self )
                        self:resetClock()
                end
                
                LUTask:yield()
        until self:shouldRepeat() == false
        
        return self
end

return self