Designing and Maintaining Software (DAMS) - GitHub
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Designing and Maintaining Software (DAMS) - GitHub
Clear Names. Designing and Maintaining Software (DAMS). Louis Rose. Page 2. Naming is hard. âThere are only two hard t
Clear Names
Designing and Maintaining Software (DAMS) Louis Rose
Naming is hard
“There are only two hard things in Computer Science: cache invalidation and naming things.” - Phil Karlton http://martinfowler.com/bliki/TwoHardThings.html
MAX_MODULES_PER_STUDEN T exam_number exams.each { |e| … }
Pronouncable
genymdhms
generationTimestamp
Avoid encodings
name_string int_exam_number Exam implements IExam
name exam_number ExamImpl implements Exam
Tactics Use noun phrases for classes and verb phrases for methods: ExamRoom#start_timer Avoid puns: kill is clearer than whack or eat_my_shorts Use solution domain names: AccountVisitor, JobQueue Use problem domain names ExamRoom, Examiner
Ubiquitous Language “Design calls for a versatile, shared team language, and a lively experimentation with language that seldom happens on software projects.” - Eric Evans Domain Driven Design
Emergence When refactoring, extract methods with complete nonsensical names: foo, bar, baz Begin to understand what the new methods do, so rename them: calculate, process, execute Discover that the new names are not precise, so rename them: process_cheque_and_notify_receipient Discover multiple responsibilities, so separate and attach new (possibly nonsensical names) http://blog.thecodewhisperer.com/2011/06/15/a-model-for-improving-names/ http://www.jbrains.ca/permalink/the-four-elements-of-simple-design
Summary Aim for names that have integrity and utility Use names from the solution and problem domains Names and their abstractions can (should?) co-evolve during design and maintenance
