A repeating timer in Python

repeatingtimer.py

class RepeatingTimer(object):
	"""
	USAGE:
	from time import sleep
	def myFunction(inputArgument):
		print(inputArgument)
	
	r = RepeatingTimer(0.5, myFunction, "hello")
	r.start(); sleep(2); r.interval = 0.05; sleep(2); r.stop()
	"""

	def __init__(self,interval, function, *args, **kwargs):
		super(RepeatingTimer, self).__init__()
		self.args = args
		self.kwargs = kwargs
		self.function = function
		self.interval = interval

	def start(self):
		self.callback()
		
	def stop(self):
		self.interval = False
		
	def callback(self):
		if self.interval:
			self.function(*self.args, **self.kwargs)
			Timer(self.interval, self.callback, ).start()

You could just extend the standard library class and change one line in their run() method:

from threading import _Timer


class Timer(_Timer):
    """
    See: https://hg.python.org/cpython/file/2.7/Lib/threading.py#l1079
    """

    def run(self):
        while not self.finished.is_set():
            self.finished.wait(self.interval)
            self.function(*self.args, **self.kwargs)

        self.finished.set()

^ Nice.

def run(self):
    while not self.finished.is_set():
        self.finished.wait(self.interval)
        self.function(*self.args, **self.kwargs)
    self.finished.set()

One question... What for self.finished.set() needed if program come there only if event already set.
And one more thing guys. I am trying to create timer wich can be paused and started again:

`class RXTimer( Thread ):
def init(self, interval, function, args=None, kwargs=None):
Thread.init(self)
self.interval = interval
self.function = function
self.args = args if args is not None else []
self.kwargs = kwargs if kwargs is not None else {}
self.paused = Event()
self.active = Event()
self.active.clear()
self.paused.set()

def run( self ):
    while True:
        self.active.wait()
        self.paused.clear()
        while not self.paused.set():
            self.paused.wait( self.interval )
            self.function( *self.args, **self.kwargs )
        self.active.clear()

def switch( self ):
    if self.active.is_set():
        self.paused.set()
    else:
        self.active.set()
    
def isActive( self ): return self.active.is_set()            

'`
But problem is self.paused.wait( self.interval ) do not lock thread and thread call self.function( *self.args, **self.kwargs ) without pauses.

Why?

from threading import Timer
import time

class RepeatingTimer(object):
"""
USAGE:
from time import sleep
r = RepeatingTimer(_print, 0.5, "hello")
r.start(); sleep(2); r.interval = 0.05; sleep(2); r.stop()
"""

def __init__(self, function, interval, *args, **kwargs):
    super(RepeatingTimer, self).__init__()
    self.args = args
    self.kwargs = kwargs
    self.function = function
    self.interval = interval

def start(self):
    self.callback()
    
def stop(self):
    self.interval = False
    
def callback(self):
    if self.interval:
        self.function(*self.args, **self.kwargs)
        Timer(self.interval, self.callback, ).start()

def dowork():
global count
count = count + 1

count = 0
timer = RepeatingTimer(dowork, 0.0001)
timer.start()
time.sleep(1.0)
timer.stop()

print(count)
output:
3039

The theoretical output should be 10000. But here it is 3039. I'm not understanding why!