1.
We write code

2.
Isn't it more about
reading?

3.
Written once – read many
times

4.
„(…) when you program,
you have to think about
how someone will read
your code, not just how a
computer will interpret it.“
Kent Beck

5.
Not about
Architecture

6.
Methods & Code

7.
Extra effort

8.
Save time

9.
Your code base?

10.
It's about joy!

11.
Code is read many more times
than written
Tobias Pfeiffer
@PragTob
pragtob.wordpress.com

12.
Sources

13.
Crazy?

14.
Are comments a smell?

15.
Outdated comments are the
worst

16.
The why not the what

17.
Comments are an excuse of
the code that it could not be
clearer.

18.
# do one thing
…
…
…
# do another thing
…
…
…
# do something more
…
…

19.
Extract Methods

20.
do_one_thing
do_another_thing
do_something_more

21.
# context, outlet, times, time per
step, state, data
def pattern(c, o, t, l, s, d)
# …
end

22.
Explanatory and meaningful
names

23.
def pattern(context, outlet, time,
time_per_step, state, data)
# …
end

24.
Try to keep it to 2 parameters

25.
Argument order dependency

26.
No magic numbers

27.
Explanatory variable

28.
Short Methods (<= 8 LOC)

29.
# allowed to drink?
if customer.age > 18
say 'Okay'
prepare_drink requested_drink
say 'here you go'
hand_drink_over drink, customer
else
say 'I am sorry you are not legally
allowed rather to drink here'
say "Would you rather have a
#{NON_ALCOHOLIC_DRINKS.sample}?"
end

30.
# allowed to drink?
if customer.age > 18
say 'Okay'
prepare_drink requested_drink
say 'here you go'
hand_drink_over drink, customer
else
say 'I am sorry you are not legally
allowed rather to drink here'
say "Would you rather have a
#{NON_ALCOHOLIC_DRINKS.sample}?"
end

31.
Query method

32.
Intention revealing method

33.
# …
text.color = red
# …

34.
def highlight(text)
text.color = red
end

35.
# …
highlight(text)
# …

36.
if customer.age > 18
say 'Okay'
prepare_drink requested_drink
say 'here you go'
hand_drink_over drink, customer
else
say 'I am sorry you are not legally
allowed rather to drink here'
say "Would you rather have a
#{NON_ALCOHOLIC_DRINKS.sample}?"
end

37.
if customer.age > 18
say 'Okay'
prepare_drink requested_drink
say 'here you go'
hand_drink_over drink, customer
else
say 'I am sorry you are not legally
allowed rather to drink here'
say "Would you rather have a
#{NON_ALCOHOLIC_DRINKS.sample}?"
end

38.
if customer.age > 18
say 'Okay'
prepare_drink requested_drink
say 'here you go'
hand_drink_over drink, customer
else
say 'I am sorry you are not legally
allowed rather to drink here'
say "Would you rather have a
#{NON_ALCOHOLIC_DRINKS.sample}?"
end

39.
if customer.age > 18
say 'Okay'
prepare_drink requested_drink
say 'here you go'
hand_drink_over drink, customer
else
say 'I am sorry you are not legally
allowed rather to drink here'
say "Would you rather have a
#{NON_ALCOHOLIC_DRINKS.sample}?"
end

40.
if allowed_to_drink_alcohol?(customer)
serve_drink requested_drink,
customer
else
propose_non_alcoholic_drink
end

41.
„The easiest code to
understand is the code you
don't have to read at all.“
Tom Stuart (Berlin)

42.
Same level of abstraction in a
method

43.
prepare_drink requested_drink
price = requested_drink.price
Check = Check.new
check.add_price price
say 'That whill be ' + check.total

44.
prepare_drink requested_drink
price = requested_drink.price
Check = Check.new
check.add_price price
say 'That whill be ' + check.total

45.
prepare_drink requested_drink
price = requested_drink.price
Check = Check.new
check.add_price price
say 'That whill be ' + check.total

46.
prepare_drink requested_drink
prepare_check requested_drink

47.
DRY

48.
Nice code formatting

49.
@left ||= 0
@top ||= 0
@width ||= 1.0
@height ||= 0

50.
double character: 'something weird',
stateMask: CTRL | modifier,
KeyCode: character.downcase.ord

51.
80 character
Width limit

52.
80 character
Width limit

53.
80 character
Width limit

54.
80 character
Width limit

55.
80 character
Width limit

56.
Don't program by coincedence

57.
Code bases detoriate

58.
No broken windows

59.
Magical time?

60.
The Boyscout
Rule

61.
TDD

62.
80% Code Coverage

63.
20% is never executed

64.
„Incoming messages should be tested for
the state they return. Outgoing
command messages should be tested
to ensure they get sent. Outgoing query
messages should not be tested.“
Sandi Metz

65.
Know when to
break the rules

66.
If you still like your code from
two years ago,
then you are not learning fast
enough.

67.
Enjoy Coding!
Tobias Pfeiffer
@PragTob
pragtob.wordpress.com

68.
Sources
● The Pragmatic Programmer
● Smalltalk Best Practice Patterns
● Clean Code
● Practical Object Oriented Design in Ruby

69.
Photo Credit
●
http://officeimg.vo.msecnd.net/en-us/images/MP900439313.jpg
●
http://officeimg.vo.msecnd.net/en-us/images/MC900021328.wmf
●
(CC BY-SA 2.0)
– http://www.flickr.com/photos/83633410@N07/7658272558/in/photostream/
– http://www.flickr.com/photos/83633410@N07/7658165122/
– http://en.wikipedia.org/wiki/File:Kent_Beck_no_Workshop_Mapping_XP.jpg
●
(CC BY-NC-ND 2.0)
– http://www.flickr.com/photos/andih/86577529/
– http://www.flickr.com/photos/12584908@N08/3293117576/
– http://www.flickr.com/photos/jasonlparks/4525188865/
– http://www.flickr.com/photos/20714221@N04/2293045156/
●
http://www.flickr.com/photos/47833351@N02/5488791911/(CC BY-ND 2.0)
●
(CC BY 2.0)
– http://www.flickr.com/photos/barry_b/76055201/
– http://www.flickr.com/photos/25165196@N08/7725273678/
– http://www.flickr.com/photos/29254399@N08/3187186308/
●
(CC BY-NC-SA 2.0)
– http://www.flickr.com/photos/dolescum/7380616658/
– http://www.flickr.com/photos/antonkovalyov/5795281215/
– http://www.flickr.com/photos/doug88888/2792209612/
●
(CC BY-NC 2.0)
– http://www.flickr.com/photos/37996583811@N01/5757983532/
– http://www.flickr.com/photos/sevendead/5650065458/

70.
Source pictures
● http://imagery.pragprog.com/products/59/tpp.jpg
● http://www.informit.com/ShowCover.aspx?isbn=9780132852111&type=f
● http://coding-in.net/blog/wp-content/uploads/clean_code.jpg
● http://www.informit.com/ShowCover.aspx?isbn=9780321721334&type=f
● http://mendicantuniversity.org/images/logo.png