Bug #5405 ยป 0001-adding-documentation-for-Hash.patch
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}
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/*
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* A <code>Hash</code> is a collection of key-value pairs. It is
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* similar to an <code>Array</code>, except that indexing is done via
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* arbitrary keys of any object type, not an integer index. Hashes enumerate
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* their values in the order that the corresponding keys were inserted.
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* A <code>Hash</code> is a dictionary-like collection of unique keys and
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* their values. Also called associative arrays, they are similar to
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* Arrays, but where an <code>Array</code> uses integers
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* as its index, a <code>Hash</code> allows you to use any object type.
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*
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* Hashes enumerate their values in the order that
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* the corresponding keys were inserted.
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*
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* A Hash can be easily created by using its implicit form:
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*
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* grades = {"Jane Doe" => 10, "Jim Doe" => 6}
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*
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* Hashes allow an alternate syntax form when your keys are always symbols.
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* Instead of
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*
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* options = {:font_size => 10, :font_family => "Arial"}
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*
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* You could write it as:
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*
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* options = {font_size: 10, font_family: "Arial"}
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*
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* Each named key is a symbol you can access in hash:
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*
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* options[:font_size] #=> 10
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*
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* A Hash can also be created through its <code>new</code> method:
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*
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* grades = Hash.new
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* grades["Dorothy Doe"] = 9
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*
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* Hashes have a <em>default value</em> that is returned when accessing
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* keys that do not exist in the hash. By default, that value is
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* <code>nil</code>.
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* <code>nil</code>. You can setup its default value by sending it as
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* an argument on the Hash initialization:
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*
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* grades = Hash.new(0)
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*
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* Or by using its <code>default</code> method:
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*
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* grades = {"Timmy Doe" => 8}
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* grades.default = 0
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*
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* Accessing a Hash requires using its key:
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*
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* puts grades["Jane Doe"] #=> 10
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*
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* === Common Uses
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*
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* Hashes are an easy way to represent data structures, such as
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*
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* books = {}
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* books[:matz] = "The Ruby Language"
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* books[:black] = "The Well-Grounded Rubyist"
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*
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* Hashes are also commonly used as a way to have named parameters
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* in functions. Note that no brackes are used below. If a hash is
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* the last argument on a method call, no braces are needed,
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* thus creating a really clean interface:
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*
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* Person.create(name: "John Doe", age: 27)
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*
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* def self.create(params)
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* @name = params[:name]
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* @age = params[:age]
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* end
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*
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*
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*/
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