I am struggling to make a piece of code that allows to measure time spent within a "with" statement and assigns the time measured (a float) to the variable provided in the "with" statement.
import time
class catchtime:
def __enter__(self):
self.t = time.clock()
return 1
def __exit__(self, type, value, traceback):
return time.clock() - self.t
with catchtime() as t:
pass
This code leaves t=1 and not the difference between clock() calls. How to approach this problem? I need a way to assign a new value from within the exit method.
PEP 343 describes in more detail how contect manager works but I do not understand most of it.
Solved (almost). Resulting variable is coercible and convertible to a float (but not a float itself).
class catchtime:
def __enter__(self):
self.t = time.clock()
return self
def __exit__(self, type, value, traceback):
self.e = time.clock()
def __float__(self):
return float(self.e - self.t)
def __coerce__(self, other):
return (float(self), other)
def __str__(self):
return str(float(self))
def __repr__(self):
return str(float(self))
with catchtime() as t:
pass
print t
print repr(t)
print float(t)
print 0+t
print 1*t
1.10000000001e-05
1.10000000001e-05
1.10000000001e-05
1.10000000001e-05
1.10000000001e-05