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    <p>For your first question, the answer is that it makes an array of its parameters.</p> <p>For your second, I have no clue, but it's simple enough.</p> <p>For your third, here it is: In Ruby, defining a global method with the same name as the class is considered good form only when used to construct or convert from object of that type of a more fundamental type. You should not define this method unless you are creating some sort of low type. You could define this for some class like <code>BigInt128</code> but you shouldn't for <code>ObscureOrSpecializedType678</code>. There is also a design for these methods.</p> <p>If the data that you are passed is of the returned type, return it. If the data is of a directly related type, perform obvious conversions (<code>Fixnum</code> to <code>BigInt128</code>). If the data passed in can be converted and is somewhat related (<code>String</code> to <code>Fixnum</code>) convert it (this conversion is usually only for <code>String</code>). If the data can not be converted, throw an exception. You should <strong>NEVER</strong> return a "magic value".</p> <p>The other use of this method is to create a semi-literal syntax for non-literal types. The best examples of this are <code>Rational()</code> and <code>Complex()</code>. These functions, in addition to doing conversions, allow you to create rations and complex numbers in a more natural way (<code>Rational(1, 2)</code> vs. <code>Rational.new(1, 2)</code>). If there is a certain argument list that is simpler to the literal representation of a type, you would define a <code>Classname()</code> method.</p> <p>For the most part, these methods are only part of the core language, and unless you are making a class like <code>BigInt128</code> or <code>FancyString</code> or <code>NaturalNumber</code>, you should not define these methods.</p> <hr> <p>From what I know the defined of these are:</p> <ul> <li><code>Array(*args)</code> -- Returns arguments as an array</li> <li><code>Complex(real, complex)</code> -- Create a complex number with given real and complex parts</li> <li><code>Float(arg)</code> -- Returns <code>arg</code> converted to a float (takes things like strings too)</li> <li><code>Integer(arg)</code> -- Same as <code>Float()</code>, but converts to an integer(floats are truncated)</li> <li><code>Rational(numerator, denominator=1)</code> -- Creates a Rational number with the given parts</li> <li><code>String(arg)</code> -- Converts argument to string by calling <code>to_s</code></li> </ul> <p>Also, some classes define <code>[]</code> as a class method, which is used for more complex initialization from basic data types (usual initialization only, not conversion) such as <code>Hash[]</code>.</p>
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    1. POwhere is the documentation for Array()?
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    1. POwhere is the documentation for Array()?
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    1. COWhy so many downvotes? I think this answers the question.
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