The document discusses the concept of connascence, which refers to coupling between software components where a change in one component requires changes in other components to maintain correctness. It defines 9 types of connascence based on different aspects that coupled components may rely on, such as identity, value, timing, etc. It also describes 3 axes (strength, degree, locality) for analyzing connascence issues. Examples are provided to illustrate different types of connascence.

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Connascence
1) Definition
2) Types
3) Examples and Usage

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Connascence
1) Definition
2) Types
3) Examples and Usage
Propose!

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At the outset...
DRY BEM
Design Patterns
Modularity
No magic numbers
KISS

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Connascence
- taxonomy for different types of coupling
- software quality metric

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Definition

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Definition
● (1995) Meilir Page-Jones;
“In software engineering, two components are connascent
if a change in one would require the other to be modified in
order to maintain the overall correctness of the system.”

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Definition
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
● Connascence of Execution Order
● Connascence of Position
● Connascence of Algorithm
● Connascence of Meaning
● Connascence of Type
● Connascence of Name
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
● Connascence of Execution Order
● Connascence of Position
● Connascence of Algorithm
● Connascence of Meaning
● Connascence of Type
● Connascence of Name

9. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Definition
Types of connascence:
● Connascence of Identity
● Connascence of Value
● Connascence of Timing
● Connascence of Execution Order
● Connascence of Position
● Connascence of Algorithm
● Connascence of Meaning
● Connascence of Type
● Connascence of Name
Types of connascence:
● Connascence of Identity
● Connascence of Value
● Connascence of Timing
● Connascence of Execution Order
● Connascence of Position
● Connascence of Algorithm
● Connascence of Meaning
● Connascence of Type
● Connascence of Name

10. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Definition
Types of connascence:
● Connascence of Identity
● Connascence of Value
● Connascence of Timing
● Connascence of Execution Order
● Connascence of Position
● Connascence of Algorithm
● Connascence of Meaning
● Connascence of Type
● Connascence of Name
Types of connascence:
● Connascence of Identity
● Connascence of Value
● Connascence of Timing
● Connascence of Execution Order
● Connascence of Position
● Connascence of Algorithm
● Connascence of Meaning
● Connascence of Type
● Connascence of Name
Direction where to refactor to

11. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Definition
Types of connascence:
● Connascence of Identity
● Connascence of Value
● Connascence of Timing
● Connascence of Execution Order
● Connascence of Position
● Connascence of Algorithm
● Connascence of Meaning
● Connascence of Type
● Connascence of Name
Types of connascence:
● Connascence of Identity
● Connascence of Value
● Connascence of Timing
● Connascence of Execution Order
● Connascence of Position
● Connascence of Algorithm
● Connascence of Meaning
● Connascence of Type
● Connascence of Name
Direction where to refactor to

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Definition
Three axis of connascence:
● Strength:
Stronger connascence are harder to discover, or
harder to refactor
● Degree:
An entity that is connascent with thousands of
other entities is likely to be a larger issue than one
that is connascent with only a few.
● Locality:
Connascent elements that are close together in a
codebase are better than ones that are far apart
Strength
Weak Strong
Degree
Few A lotFew A lot
Locality
Close Far apart

13. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Definition
Three axis of connascence:
● Strength:
Stronger connascence are harder to discover, or
harder to refactor
● Degree:
An entity that is connascent with thousands of
other entities is likely to be a larger issue than one
that is connascent with only a few.
● Locality:
Connascent elements that are close together in a
codebase are better than ones that are far apart
Direction where to refactor to
Strength
Weak Strong
Degree
Few A lotFew A lot
Locality
Close Far apart

14. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Definition
Three axis of connascence:
● Strength:
Stronger connascence are harder to discover, or
harder to refactor
● Degree:
An entity that is connascent with thousands of
other entities is likely to be a larger issue than one
that is connascent with only a few.
● Locality:
Connascent elements that are close together in a
codebase are better than ones that are far apart
Direction where to refactor to
Strength
Weak Strong
Degree
Few A lotFew A lot
Locality
Close Far apart

15. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Types of Connascences:
Identity
Value
Timing
Execution Order
-----------------
Position
Algorithm
Meaning
Type
Name
Strength Degree
Locality

16. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Types of Connascences:
Identity
Value
Timing
Execution Order
-----------------
Position
Algorithm
Meaning
Type
Name
Strength Degree
Locality

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Types

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Connassence of Name
● Two components must agree on the name of
something
● Locality close*
*same file

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Connassence of Name
● Two components must agree on the name of
something
● Locality close*
*same file

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Connassence of Name
● Two components must agree on the name of
something
● Locality further apart

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Connassence of Type
● Two components must agree on the type of
something

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Connassence of Type
● Two components must agree on the type of
something
● ...it happens for strong typed languages too:

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Connassence of Meaning
● Two components must agree on the
interpretation of a value

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Connassence of Meaning
● Two components must agree on the
interpretation of a value
Aka. “magical number”

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Connassence of Position
● Two components must be adjacent or occur in
a particluar order
● 3 degrees of connascence

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Connassence of Position
● Two components must be adjacent or occur in
a particluar order

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Connassence of Algorithm
● Two components must agree on a particular
algorithm
- Encryption, e.g. SHA-2, SHA512, etc
- Certificate

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Connassence of Execution Order
● The order of execution of two components is
important

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Connassence of Timing
● Two components must agree on the timing of
execution
E.g. Race condition between threads

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Connassence of Value
● Several values have to change together
● Locality further apart

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Connassence of Identity
● Two components must reference the same
entity

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Examples

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Examples
Types of connascence:
● Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
●
Connascence of Type
●
Connascence of Name
Types of connascence:
● Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
●
Connascence of Type
●
Connascence of Name

34. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Examples
Types of connascence:
● Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
●
Connascence of Type
●
Connascence of Name
Types of connascence:
● Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
●
Connascence of Type
●
Connascence of Name

35. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Examples
Types of connascence:
● Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
●
Connascence of Type
●
Connascence of Name
Types of connascence:
● Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
●
Connascence of Type
●
Connascence of Name

36. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Examples
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name

37. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Examples
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name

38. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Examples
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name

39. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Examples
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name

40. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Examples
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name
*still connascence. of value, but locality close

41. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Examples
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name
Types of connascence:
●
Connascence of Identity
●
Connascence of Value
●
Connascence of Timing
●
Connascence of Execution Order
●
Connascence of Position
●
Connascence of Algorithm
●
Connascence of Meaning
● Connascence of Type
● Connascence of Name

42. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Usage

43. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Usage
● Gives me a way to evaluate and prioritize code
review/refactor (now I don’t do fixes that are
easiest but the most risky)
● New tool to communicate (good reviews aren’t
based on personal taste but on objective metric)
● Gives new developers a
framework/compass/guidance for writing good,
clean, and maintainable code

44. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Usage
● Gives me a way to evaluate and prioritize code
review/refactor (now I don’t do fixes that are
easiest but the most risky)
● New tool to communicate (good reviews aren’t
based on personal taste but on objective metric)
● Gives new developers a
framework/compass/guidance for writing good,
clean, and maintainable code
Propose!

45. @PandaScriptCom @thadeuszlay linkedin.com/in/trung-thanh-le/ PandaScript.com thanh.le@sinnerschrader.com
Sources
● “What every Software Developer should know about
Object-Oriented Programming” by Meilir Page-Jones
● ETE 2012 - Jim Weirich - Connascence Examined:
https://www.youtube.com/watch?v=NLT7Qcn_PmI
● Codemania 2015: Josh Robb - Connascence &
Coupling:
https://www.youtube.com/watch?v=Ip2o4vbAK3s