31 lines
1.1 KiB
Markdown
31 lines
1.1 KiB
Markdown
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---
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title: Learn About Ruby Hashes
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---
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### Basics:
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* Ruby hashes are comparable to Javascript objects or dictionaries in languages like Python.
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* Hashes contain items that are stored by `key: value` pairs.
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* Ruby hashes can be created using the following methods:
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* `my_hash = {}`
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* `my_hash = Hash.new`
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* There are many methods built into Ruby to find information from and update hashes.
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## Examples:
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my_hash = {'name' => 'Batman', 'age' => 25}
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# is equivalent to:
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my_hash = Hash.new
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my_hash<a href='http://www.randomhacks.net/2007/01/20/13-ways-of-looking-at-a-ruby-symbol/' target='_blank' rel='nofollow'>'name'] = 'Batman'
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my_hash['age'] = 25
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# Both of these examples return:
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{"name"=>"Batman", "age"=>25}
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# here is an alternative way to create the array:
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{name: 'Batman', age: 25}
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# this example return:
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{:name=>"Batman", :age=>25}
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# learn more about [symbols here</a>
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## References:
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* <a href='http://ruby-doc.org/core-2.2.0/Hash.html' target='_blank' rel='nofollow'>The official Ruby documentation for hashes</a>.
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