Bug #11555 ยป document-class-numeric.patch
numeric.c | ||
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*/
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/*
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* The top-level number class.
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* Document-class: Numeric
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*
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* Numeric is the class from which all higher-level numeric classes should inherit.
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*
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* Numeric allows instantiation of heap-allocated objects. Other core numeric classes such as
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* Integer are implemented as immediates, which means that each Integer is a single immutable
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* object which is always passed by value.
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*
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* a = 1
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* puts 1.object_id == a.object_id #=> true
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*
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* There can only ever be one instance of the integer +1+, for example. Ruby ensures this
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* by preventing instantiation and duplication.
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*
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* Integer.new(1) #=> NoMethodError: undefined method `new' for Integer:Class
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* 1.dup #=> TypeError: can't dup Fixnum
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*
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* For this reason, Numeric should be used when defining other numeric classes.
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*
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* Classes which inherit from Numeric must implement +coerce+, which returns a two-member
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* Array containing an object that has been coerced into an instance of the new class
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* and +self+ (see #coerce).
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*
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* Inheriting classes should also implement arithmetic operator methods (<code>+</code>,
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* <code>-</code>, <code>*</code> and <code>/</code>) and the <code><=></code> operator (see
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* Comparable). These methods may rely on +coerce+ to ensure interoperability with
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* instances of other numeric classes.
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*
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* class Tally < Numeric
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* def initialize(string)
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* @string = string
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* end
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*
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* def to_s
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* @string
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* end
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*
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* def to_i
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* @string.size
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* end
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*
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* def coerce(other)
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* [self.class.new('|' * other.to_i), self]
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* end
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*
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* def <=>(other)
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* to_i <=> other.to_i
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* end
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*
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* def +(other)
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* self.class.new('|' * (to_i + other.to_i))
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* end
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*
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* def -(other)
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* self.class.new('|' * (to_i - other.to_i))
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* end
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*
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* def *(other)
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* self.class.new('|' * (to_i * other.to_i))
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* end
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*
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* def /(other)
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* self.class.new('|' * (to_i / other.to_i))
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* end
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* end
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*
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* tally = Tally.new('||')
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* puts tally * 2 #=> "||||"
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* puts tally > 1 #=> true
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*/
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void
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Init_Numeric(void)
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