39 lines
739 B
Markdown
39 lines
739 B
Markdown
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# Reduce vs Each With Object
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Both methods serve the same purpose : from an Enumerator create a single value
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out of it
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## Reduce
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Reduce is prefered when you need to produce a simple value because it reduce over the returned value
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```ruby
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[1, 2, 3].reduce(:+)
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> 3
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```
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We can illustrate this simply with this snippet :
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```ruby
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[1, 2, 3].reduce do |acc, v|
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acc += v
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0
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end
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> 0
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```
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## Each With Object
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Each with object is prefered when you reduce on a hash or some sort of complex
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object beacause is use the accumulator value and not the returned one
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```ruby
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[1, 2, 3].each_with_object({ sum: 0 }) do |v, acc|
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acc[:sum] += v
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0
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end
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> {sum: 6}
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```
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**Fun fact**, `reduce` takes `|acc, v|` while `each_with_object` take `|v, acc|`
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