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principles:principle_of_least_surprise

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Principle Of Least Surprise (PLS)

Variants and Alternative Names

  • Principle of Least Astonishment (PLA)
  • May also be referred to as “rule” or “law” instead of “principle”

Context

Principle Statement

In interface design, always do the least surprising thing.1)

Description

Rationale

Strategies

Origin

Evidence

Relations to Other Principles

Generalizations

Specializations

Contrary Principles

Complementary Principles

  • Fail Fast (FF): FF is about what a module should do in the case of error. PLS on the other hand is about how the module should behave normally. Furthermore it normally is not a surprise that a module fails when there is an error but a module that doesn't fail when it should, behaves strangely.
  • Model Principle (MP): PLS is mainly about how module identifier and module behavior relate to each other. MP tells that modules named according to the model are least surprising.
  • Uniformity Principle (UP): When applying PLS, UP should also be considered for naming modules.

Principle Collections

OOD Principle Language
General Principles
ML KISS MIMC DRY GP RoE
Modularization Principles
MP HC ECV
Module Communication Principles
TdA/IE LC DIP
Interface Design Principles
EUHM PLS UP
Internal Module Design Principles
IH/E IAP LSP PSU

Example

Description Status

Further Reading

principles/principle_of_least_surprise.1360529577.txt.gz · Last modified: 2013-05-20 12:46 (external edit)