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36 lines
641 B
Markdown
36 lines
641 B
Markdown
# Construct A Constant From A String
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Ruby's
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[`Module.const_get`](http://ruby-doc.org/core-2.1.0/Module.html#method-i-const_get)
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can be used to look for and retrieve the constant for a given name.
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This can be used to construct a class name
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```ruby
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> Object.const_get("Math")
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#=> Math
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> Object.const_get("Math")::PI
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#=> 3.141592653589793
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```
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It can also be used to reference a constant
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```ruby
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> Object.const_get("Math::PI")
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#=> 3.141592653589793
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```
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You can even be more specific if you'd like
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```ruby
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> Math.const_get("PI")
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#=> 3.141592653589793
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```
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Symbols are valid as well
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```ruby
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> Math.const_get(:PI)
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#=> 3.141592653589793
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```
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