The document discusses the importance of naming in code. It states that naming matters as it signifies potential problems in design and shortens the learning curve. It also discusses different types of bad names like vague names that don't express a role, abbreviations that are ambiguous, names that are too long to remember, and names that include unnecessary context. The document emphasizes that names should reference terms from the domain model and be written like well-written prose using classes as nouns, methods as verbs, interfaces as adjectives, and booleans as auxiliary verbs. It concludes with six reminders for good naming practices.

1. linkedin/borislit github.com/borislit@borislitborisl@wix.com
Name in Vain
Improving design one word at a time

2. Hi.
I am Boris Litvinsky
Frontend Developer @ WIX Bookings
Lithuania
Ukraine
Vilnius
Kiev
Dnipro
Wix Engineering Locations
Israel
Tel-Aviv
Be’er Sheva

3. Readable
Code
01

4. Readable by Computer
is Easy

5. Readable by Humans
is Difficult

6. It’s much more like
studying 17th century
French poetry -
WTF did this guy mean?
“
“
“
David Heinemeier Hansson

7. You can name
your kid anything
you want.
There are no laws.
There should be
couple of laws
- Louis CK
“
“

8. Naming
Matters
02

9. Naming Matters
▪ Discussing Names = Discussing the Product
▪ May signify a problem in a design
▪ Shortens the learning curve
▪ “The Six Month Rule”
http://blog.marcomonteiro.net/post/the-six-months-rule

10. The reason that they think
the old code is a mess is
because of a fundamental
law of programming:
It’s harder to read code
than to write it.
“
“
“
David Heinemeier HanssonJoel Spolsky

11. Anatomy of
Bad Names
03

12. Vague, Meaningless Names
▪ Your “Managers”, Your “Services”, Your “Handler”
▪ Your “object”, Your “data”
Don't express
their role in
the system
Eventually
become a
bag of
methods
Usually cause
SRP violation
=
Increase size
& coupling
Don't express
their role in
the system
Eventually
become a
bag of
methods

13. Abbreviations are Ambitious
▪ char - is it a “character” or “characteristic” ?
▪ mod - is it “modify” or “modulo”?
Compels you
to read the
code
You can’t use
them in a
conversation
Compels you
to read the
code

14. Too Many Words
▪ dontTryToWriteWholeSentencesWithYourDamnFunctionName
▪ How is “company_person” better than “employee” ?
http://wiki.c2.com/?MeaningfulName
http://hilton.org.uk/blog/naming-smells
Difficult to
remember
Difficult to
spot differences
Difficult to
remember
oneHorribleDescriptiveLongNameVersion
vs
oneHorribleDestructiveLongSameVersion
You probably
don’t know
what it is
You probably
don’t know
what it is

15. × ✓car.startEngine() car.start()
Excess Nouns in Function Names
Nouns are
implementation
details, that the
caller knows
about
▪ Perfectly fine if the noun is one of the parameters, e.g.,
car.startPowerProvider(powerProvider)
▪ Getters are horrible

16. Too Much Context
×
✓
class PendingPaymentRecord() {}
class PaymentRecord() {}
Prevents
reuse of
objects/meth
ods in other
valid cases

17. We Resolve to Basic Instincts

18. Lack of Domain Knowledge
Domain - A subject the software is being developed for.

19. But...
▪ How can you build software without understanding the problem it’s solving?
▪ How can you apply new requirements to software that doesn't reflect the domain?
▪ How can you name something you don’t understand?

21. Consumer Vocabulary
Domain Model
A simplified representation of
domain knowledge.
* Created by software expert & domain expert
Defines a
Ubiquitous
Language -
vocabulary used
by everybody,
everywhere

22. Names should reference the
Ubiquitous Language

24. Clean code reads like
well-written prose
“ “
“
David Heinemeier HanssonRobert C. Martin

25. Well Written Prose
“Prose is a form of
language that exhibits a
grammatical structure and
a natural flow of speech” -
Wikipedia
https://en.wikipedia.org/wiki/Prose
https://www.citerus.se/specification-pattern-as-a-re
factoring-tool
//Example 1
if(car.speed() > 2 * SPEED_LIMIT) {
speaker.generateAlert('Police reported ahead');
}
//Example 2
const candidateCarSpecification = colorRed
.and(inApprovedCity.or(convertible));
if (candidateCarSpecification.isSatisfiedBy(car)) {
//...
}

26. Classes Nouns
● Should describe the role it fulfils in the system
● Should allow the class to be easily located and evaluated

27. Methods
▪ Help us identify additional responsibilities, e.g., DoesThisAndThat()
https://www.youtube.com/watch?v=4cVZvoFGJTU&t=239s
RuleEvaluator
+evaluate(string)
-parseAdjunctTerm()
-parseFactorTerm()
-parseAdjunct()
-hasMoreTokens()
-getNextToken()
RuleEvaluator
+evaluate(string)
-parseAdjunctTerm()
-parseFactorTerm()
-parseAdjunct()
RuleTokenizer
+hasMoreTokens()
+getNextToken()

28. Methods
▪ Help us identify additional responsibilities
▪ Those without side-effects should read as noun e.g player.balance()
▪ Those with side-effects should read as verbs e.g player.start()
▪ Can include prepositions (Of, To, For) to help describe relationships to
parameters e.g payAmountOf(...) or moveTo(...)
▪ Describe everything it does - no surprises!

29. Interfaces Adjectives
▪ There’s no “I” in Interface
▪ Describes a capability
▪ Deliverable, Shippable, Printable

30. Booleans Auxiliary / Helping Verbs
▪ is, should, can, has
▪ if( piece.isOn(square) ) {...}
if( player.hasBalanceOf(amount) ) {...}
if( player.canPurchase(property) ) {...}

31. 6 Things to Remember
★
Renaming
is part of
refactoring!
★
Use the
consumer’s
vocabulary
★
Make sure you
can read what
you write
★
Be open for
feedback
★
Communicate
names/renames
to other people.
Be consistent
Don’t give up!
Struggle for every word.

32. Thank You
linkedin/borislit github.com/borislit@borislitborisl@wix.com

33. Q&A
linkedin/borislit github.com/borislit@borislitborisl@wix.com