2.2 Writing long lines of code

There are many times when we need to write lines of code that are so long that they’re very hard to read. Many people like to limit the length of a line of code to 80 characters or fewer. It’s a well-known principle of graphic design that a narrower area of text is easier to read. See http://webtypography.net/2.1.2 for a deeper discussion of line width and readability.

While fewer characters per line is easier on the eyes, our code can refuse to cooperate with this principle. How can we break long Python statements into more manageable pieces?

2.2.1 Getting ready

Let’s say we’ve got something like this:

>>> import math
>>> example_value = (63/25) * (17+15*math.sqrt(5)) / (7+15*math.sqrt(5))
>>> mantissa_fraction, exponent = math.frexp(example_value)
>>> mantissa_whole = int(mantissa_fraction*2**53)
>>> message_text = f’...