Bug #15405 ยป endless-range.patch
| doc/syntax/literals.rdoc | ||
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(1..2) # includes its ending value
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(1...2) # excludes its ending value
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(1..) # endless range, representing infinite sequence from 1 to Infinity
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You may create a range of any object. See the Range documentation for details
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on the methods you need to implement.
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| range.c | ||
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* ('a'..'e').to_a #=> ["a", "b", "c", "d", "e"]
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* ('a'...'e').to_a #=> ["a", "b", "c", "d"]
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*
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* == Endless Ranges
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*
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* Since Ruby 2.6, there is an "endless range" concept, representing
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* half-infinite ranges. Literal for an endless range is:
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*
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* (1..)
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*
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* Which is equivalent to
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*
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* (1..nil)
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* # or
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* Range.new(1, nil)
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*
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* Endless ranges are useful, for example, for idiomatic slicing of
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* arrays:
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*
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* [1, 2, 3, 4, 5][2..] # => [3, 4, 5]
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*
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* Some implementation details:
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*
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* * +end+ of endless range is +nil+;
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* * +size+ of endless numeric range is +Infinity+;
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* * +to_a+ of endless range raises +RangeError+;
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* * +each+ of endless range enumerates infinite sequence (may be
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* useful in combination with Enumerable#take_while or similar
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* methods);
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* * <code>(1..)</code> and <code>(1...)</code> are NOT equal,
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* although technically representing the same sequence.
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*
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* == Custom Objects in Ranges
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*
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* Ranges can be constructed using any objects that can be compared
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