IS MISUNDERSTOOD Steven Solomon Senior Software Engineer @ Pivotal - - PowerPoint PPT Presentation

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IS MISUNDERSTOOD Steven Solomon Senior Software Engineer @ Pivotal - - PowerPoint PPT Presentation

Sep 28, 2023 187 likes •1.29k views

THE DRY PRINCIPLE IS MISUNDERSTOOD Steven Solomon Senior Software Engineer @ Pivotal Labs Twitter: @ssolo112 Medium: @ssolomon DRY PRINCIPLE GROCERY APPLICATION By Annie Spratt on Unsplash WHAT IS IN THE APPLICATION? Dry Goods Produce

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THE DRY PRINCIPLE IS MISUNDERSTOOD

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Steven Solomon

Senior Software Engineer @ Pivotal Labs Twitter: @ssolo112 Medium: @ssolomon

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DRY PRINCIPLE

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SLIDE 4 By Annie Spratt on Unsplash

GROCERY APPLICATION

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Dry Goods Produce Meats

WHAT IS IN THE APPLICATION?

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Dry Goods Produce Meats

Margin: 300% Margin: 200% Margin: 100%

PRICING GROCERIES

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# produce.rb class Produce def initialize(cost) @cost = cost end def price psychological_price(@cost * BigDecimal('100')) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

PRODUCE

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# dry_good.rb class DryGood def initialize(cost) @cost = cost end def price psychological_price(@cost * BigDecimal(‘200')) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

DRY GOOD

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# meat.rb class Meat def initialize(cost) @cost = cost end def price psychological_price(@cost * BigDecimal(‘300')) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

MEAT

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“

DRY Principle is about removing duplicate code

  • Grocery App Developers
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SLIDE 11 By Annie Spratt on Unsplash

GROCERY APPLICATION

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SLIDE 12 class Meat def initialize(cost) @cost = cost end def price psychological_price(@cost * BigDecimal('300')) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end class Produce def initialize(cost) @cost = cost end def price psychological_price(@cost * BigDecimal('100')) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end class DryGood def initialize(cost) @cost = cost end def price psychological_price(@cost * BigDecimal('200')) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

REMOVING CODE DUPLICATION

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SLIDE 13 class Meat def initialize(cost) @cost = cost end def price psychological_price(@cost * BigDecimal('300')) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end class Produce def initialize(cost) @cost = cost end def price psychological_price(@cost * BigDecimal('100')) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end class DryGood def initialize(cost) @cost = cost end def price psychological_price(@cost * BigDecimal('200')) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

REMOVING CODE DUPLICATION

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# priceable.rb module Priceable def price psychological_price(@cost * @margin) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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# priceable.rb module Priceable def price psychological_price(@cost * @margin) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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SLIDE 16 # produce.rb class Produce include Priceable def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end end # meat.rb class Meat include Priceable def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end end # dry_good.rb class DryGood include Priceable def initialize(cost) @cost = cost @margin = BigDecimal('200') end end
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SLIDE 17 # produce.rb class Produce include Priceable def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end end # meat.rb class Meat include Priceable def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end end # dry_good.rb class DryGood include Priceable def initialize(cost) @cost = cost @margin = BigDecimal('200') end end
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SLIDE 18 Djim Loic on Unsplash
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SLIDE 19 Ricardo Viana on Unsplash
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# priceable.rb module Priceable def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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WHY DID THIS HAPPEN?

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THE DRY PRINCIPLE IS NOT ABOUT DUPLICATE CODE

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WHAT IS THE DRY PRINCIPLE REALLY ABOUT?

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“

Every piece of knowledge must have a single, unambiguous, authoritative representation within a system

  • Dave Thomas & Andy Hunt
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TECHNIQUES

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TALKING TO THE PRODUCT TEAM

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BALANCED TEAM

Product Design Software

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BALANCED TEAM LANGUAGE

Business User Technical

Balanced Language

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BALANCED TEAM LANGUAGE

Business User Technical

Balanced Language

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SLIDE 30 Mark Rabe - Unsplash
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Meat Produce Priceable

:price

DryGood

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Meat Produce Priceable

:price

DryGood

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Meat Produce Priceable

:price

DryGood

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Meat Produce Priceable

:price

DryGood

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Meat Produce

:price

DryGood

:price :price

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Business User Technical

BALANCED TEAM LANGUAGE

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Business User Technical

DryGood Produce Meat

BALANCED TEAM LANGUAGE

Priceable

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Business User Technical

Priceable

BALANCED TEAM LANGUAGE

DryGood Produce Meat

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Business User Technical

BALANCED TEAM LANGUAGE

DryGood Produce Meat

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Business User Technical

BALANCED TEAM LANGUAGE

DryGood Produce Meat

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TALKING TO THE PRODUCT TEAM

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BITS VS CLUMPS

https://www.facebook.com/notes/kent- beck/bits-clumps-and-just- right/792597974106402

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DryGood Produce

CAN I REASON ABOUT THESE SEPARATELY?

:price :price

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DryGood Produce

CAN I REASON ABOUT THESE SEPARATELY?

:price :price

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ARE THEY SEPARATE?

Produce Priceable

:price

DryGood

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ARE THEY SEPARATE?

Produce Priceable

:price

DryGood

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ARE THEY SEPARATE?

Produce Priceable

:price

DryGood

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ARE THEY SEPARATE?

Produce Priceable

:price

DryGood Priceable

:price

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ARE THEY SEPARATE?

Produce

:price

DryGood

:price

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BITS VS CLUMPS

https://www.facebook.com/notes/kent- beck/bits-clumps-and-just- right/792597974106402

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NOTICING DIVERGENT CHANGE

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SHOTGUN SURGERY

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SLIDE 53 # produce.rb class Produce include Priceable def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = 100.0 end end # meat.rb class Meat include Priceable def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = 300.0 end end # dry_good.rb class DryGood include Priceable def initialize(cost) @cost = cost @margin = 200.0 end end

SHOTGUN SURGERY

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SLIDE 54 # produce.rb class Produce include Priceable def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = 100.0 end end # meat.rb class Meat include Priceable def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = 300.0 end end # dry_good.rb class DryGood include Priceable def initialize(cost) @cost = cost @margin = 200.0 end end

SHOTGUN SURGERY

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SLIDE 55 # produce.rb class Produce include Priceable def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end end # meat.rb class Meat include Priceable def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end end # dry_good.rb class DryGood include Priceable def initialize(cost) @cost = cost @margin = BigDecimal('200') end end

SHOTGUN SURGERY

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SLIDE 56 # produce.rb class Produce include Priceable def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end end # meat.rb class Meat include Priceable def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end end # dry_good.rb class DryGood include Priceable def initialize(cost) @cost = cost @margin = BigDecimal('200') end end

SHOTGUN SURGERY

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DIVERGENT CHANGE

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# priceable.rb module Priceable def price psychological_price(@cost * @margin) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

DIVERGENT CHANGE

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# priceable.rb module Priceable def price psychological_price(@cost * @margin) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

DIVERGENT CHANGE

Steak prices are based on cut

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# priceable.rb module Priceable def price total += psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

DIVERGENT CHANGE

Steak prices are based on cut

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# priceable.rb module Priceable def price total += psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

DIVERGENT CHANGE

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# priceable.rb module Priceable def price total += psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

DIVERGENT CHANGE

Produce prices are based on season

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# priceable.rb module Priceable def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

DIVERGENT CHANGE

Produce prices are based on season

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# priceable.rb module Priceable def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

DIVERGENT CHANGE

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Shotgun Surgery Divergent Change

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NOTICING DIVERGENT CHANGE

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TECHNIQUES

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GETTING BACK TO SAFETY

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class Produce include Priceable def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end end

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class Produce include Priceable def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end end

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class Produce include Priceable def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end end

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class Produce def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end def price(season = nil) total = psychological_price(@price * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class Produce def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class Produce def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class Produce def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class Produce def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class Produce def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end def price(season = nil) total = psychological_price(@cost * @margin) season != @growing_season ? total + 1 : total end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class DryGood include Priceable def initialize(cost) @cost = cost @margin = BigDecimal('200') end end

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class DryGood include Priceable def initialize(cost) @cost = cost @margin = BigDecimal('200') end end

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class DryGood include Priceable def initialize(cost) @cost = cost @margin = BigDecimal('200') end end

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class DryGood def initialize(cost) @cost = cost @margin = BigDecimal('200') end def price(season = nil) total = psychological_price(@price * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class DryGood def initialize(cost) @cost = cost @margin = BigDecimal('200') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class DryGood def initialize(cost) @cost = cost @margin = BigDecimal('200') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class DryGood def initialize(cost) @cost = cost @margin = BigDecimal('200') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class DryGood def initialize(cost) @cost = cost @margin = BigDecimal('200') end def price() total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class DryGood def initialize(cost) @cost = cost @margin = BigDecimal('200') end def price() psychological_price(@cost * @margin) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class Meat include Priceable def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end end

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class Meat include Priceable def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end end

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class Meat include Priceable def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end end

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class Meat def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end def price(season = nil) total = psychological_price(@price * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class Meat def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class Meat def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class Meat def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class Meat def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end def price() total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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class Meat def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end def price() total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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module Priceable def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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module Priceable def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else season != @growing_season ? total + 1 : total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end

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SLIDE 101 class Meat def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end class Produce def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end def price(season = nil) total = psychological_price(@cost * @margin) if season != @growing_season total + 1 else total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end class DryGood def initialize(cost) @cost = cost @margin = BigDecimal('200') end def price(season = nil) psychological_price(@cost * @margin) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end
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SLIDE 102

“

So what is the correct abstraction?

  • You (Maybe)
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SLIDE 103 class Meat def initialize(cost, type, cut) @cost = cost @type = type @cut = cut @margin = BigDecimal('300') end def price(season = nil) total = psychological_price(@cost * @margin) if @type == :steak && @cut == :flatiron total + BigDecimal('5') else total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end class Produce def initialize(cost, growing_season) @cost = cost @growing_season = growing_season @margin = BigDecimal('100') end def price(season = nil) total = psychological_price(@cost * @margin) if season != @growing_season total + 1 else total end end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end class DryGood def initialize(cost) @cost = cost @margin = BigDecimal('200') end def price(season = nil) psychological_price(@cost * @margin) end private def psychological_price(amount) if amount.ceil == amount (amount + BigDecimal('0.50')).ceil - BigDecimal('0.01') else (amount).ceil - BigDecimal('0.01') end end end
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“

There isn’t one. We don’t have enough information.

  • Me
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SUMMARY

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➤ DRY Principle is about duplicate knowledge ➤ Techniques to identify pre-mature abstractions ➤ Talk to product team ➤ Bits vs clumps ➤ Noticing Divergent Change ➤ Remove pre-mature abstractions

WHAT WE TALKED ABOUT

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THANKS

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QUESTIONS

Steven Solomon Senior Software Engineer Twitter: @ssolo112 Medium: @ssolomon

leanpub.com/agilesoftware

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I’m writing a book. It is a software book with a story leanpub.com/agilesoftware