programming-for-dummies

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The Pros and Cons of Software Engineering
If another programmer wants to modify that same source code, the version
control program may offer four choices:
✦ It may simply lock anyone else from modifying any source code that’s
been checked out. This prevents multiple programmers from working on
different copies of the same source code.
✦ It may let another programmer check out a second copy of the source
code and make any changes to it. At this point, you wind up with two
modified copies of the same source code.
✦ When both programmers return their modified versions of the same
source code back to the repository, the version control program merges
all changes back into a single copy. This has the advantage of letting
multiple programmers work on the same source code but also has the
disadvantage that merging changes might wind up scrambling the original
source code beyond recognition.
✦ For additional protection, version control programs also archive old versions
of source code so if someone totally messes up the program, he or
she can always retrieve an earlier version of the program and start all
over again.
Version control programs are essential to coordinate the activities of multiple
programmers, although they can also be handy for individual programmers.
The main points are to
✦ Always keep a copy of your old source code (so you can retrieve it again
if necessary).
✦ Always keep your changes to the source code organized.
The Pros and Cons of Software Engineering
Programming is more than just writing code and seeing if it works. The larger
the program, the more complicated it gets, and the more tools you likely
need to keep everything organized. Can software engineering guarantee that
you’ll write better and more reliable programs? Nope.
All that software engineering techniques and practices can do is encourage
you to write programs by using proven techniques. However, it’s still possible
to follow every software engineering principle and wind up writing a confusing
program that doesn’t work.
Software engineering has improved from the early days of letting programmers
loose and hoping they wrote something useful, to today’s programming
projects with software engineering tools available to guide a project at every
step of the way.