3Functions

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In the early days of programming we composed our systems of routines and subroutines. Then, in the era of Fortran and PL/1 we composed our systems of programs, subprograms, and functions. Nowadays only the function survives from those early days. Functions are the first line of organization in any program. Writing them well is the topic of this chapter.

Consider the code in Listing 3-1. It’s hard to find a long function in FitNesse,1 but after a bit of searching I came across this one. Not only is it long, but it’s got duplicated code, lots of odd strings, and many strange and inobvious data types and APIs. See how much sense you can ...

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