class Range < Object

A Range represents an interval—a set of values with a start and an end. Ranges may be constructed using the s..e and s...e literals, or with Ranges constructed using .. run from the start to the end inclusively. Those created using ... exclude the end value. When used as an iterator, ranges return each value in the sequence.

(-1..-5).to_a [] (-5..-1).to_a [-5, -4, -3, -2, -1] ('a'..'e').to_a ["a", "b", "c", "d", "e"] ('a'...'e').to_a ["a", "b", "c", "d"]

Ranges can be constructed using objects of any type, as long as the objects can be compared using their <=> operator and they support the succ method to return the next object in sequence.

class Xs # represent a string of 'x's include Comparable attr :length def initialize(n) @length = n end def succ + 1) end def <=>(other) raise TypeError unless other.kind_of? Xs @length <=> other.length end def inspect 'x' * @length end end r = xxx..xxxxxx r.to_a [xxx, xxxx, xxxxx, xxxxxx] r.member?( true


collect, detect, each_with_index, entries, find, find_all, grep, include?, map, max, member?, min, reject, select, sort, to_a

class methods

new start, end, exclusive=false ) → aRange
Constructs a range using the given start and end. If the third parameter is omitted or is false, the range will include the end object; otherwise, it will be excluded.

instance methods

rng === anObjecttrue or false
Returns true if anObject is an element of rng, false otherwise. Conveniently, === is the comparison operator used by case statements.
case 79 when 1..50 then print "low\n" when 51..75 then print "medium\n" when 76..100 then print "high\n" end


rng.begin → anObject
Returns the first object of rng.
rng.each {| i | block } → rng
Iterates over the elements rng, passing each in turn to the block.
(10..15).each do |n| print n, ' ' end


10 11 12 13 14 15
rng.end → anObject
Returns the object that defines the end of rng. See also Range#length.
(1..10).end 10 (1...10).end 10
rng.exclude_end? → true or false
Returns true if rng excludes its end value.
rng.first → anObject
Returns the first object in rng.
rng.last → anObject
Synonym for Range#end.
rng.length → anInteger
Returns the number of objects in rng.
(1..10).length 10 (1...10).length 9
rng.size → anInteger
Synonym for Range#length.
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