snippets of python generators

gen.py

def infCount():
    """
    Infinite counter
    """
    i = 0
    while True:
        yield i
        i += 1
        
# Usage
inf = infCount()
next(inf) # 0
next(inf) # 1
next(inf) # 2


def genFib():
    """
    Fibonacci generator
    """
    a, b = 0, 1
    while True:
        yield a
        a, b, = b, a + b 

 
fib = genFib()
next(fib) # 0
next(fib) # 1
next(fib) # 1
next(fib) # 2
next(fib) # 3

send_gen.py

def infCount():
    """
    Infinite counter generator 
    that takes in a value
    """
    
    i = 0
    while True:
        val = (yield i)

        if val is not None:
            i += val
        else:
            i += 1
            
# Usage
inf = infCount()
next(inf) # 0
next(inf) # 1
next(inf) # 2
inf.send(8) # give generator a value
next(inf) # 10