But it did inspire me to come up with this little bit of Python black-magic :
def makeSection(f) :
def gen(source) :
for x in source :
yield f(x)
return gen
def makeFilter(test) :
def gen(source) :
for x in source :
if test(x) : yield x
return gen
def pipeline(generators) :
def p(source) :
old = source
for g in generators :
new = g(old)
old = new
return old
return p
t2 = makeSection(lambda x : x * 2)
t3 = makeSection(lambda x : x * 3 )
f1 = makeFilter(lambda x : (x>20))
f2 = makeFilter(lambda x : (x<50))
pipe = pipeline( [ t2 , t3 , f1 , f2 ] )
for x in pipe(range(10)) : print x
See if you can work it out, I'll probably go over it tomorrow ...
