Returns true if this specification is installable on this platform.
Add a certificate to trusted certificate list.
Returns the new String formed by calling method #inspect on each array element:
a = [:foo, 'bar', 2] a.inspect # => "[:foo, \"bar\", 2]"
Returns a new Array containing each element found both in self and in all of the given Arrays other_arrays; duplicates are omitted; items are compared using eql? (items must also implement hash correctly):
[0, 1, 2, 3].intersection([0, 1, 2], [0, 1, 3]) # => [0, 1] [0, 0, 1, 1, 2, 3].intersection([0, 1, 2], [0, 1, 3]) # => [0, 1]
Preserves order from self:
[0, 1, 2].intersection([2, 1, 0]) # => [0, 1, 2]
Returns a copy of self if no arguments given.
Related: Array#&.
Returns true if the array and other_ary have at least one element in common, otherwise returns false:
a = [ 1, 2, 3 ] b = [ 3, 4, 5 ] c = [ 5, 6, 7 ] a.intersect?(b) #=> true a.intersect?(c) #=> false
Array elements are compared using eql? (items must also implement hash correctly).
Inserts given objects before or after the element at Integer index offset; returns self.
When index is non-negative, inserts all given objects before the element at offset index:
a = [:foo, 'bar', 2] a.insert(1, :bat, :bam) # => [:foo, :bat, :bam, "bar", 2]
Extends the array if index is beyond the array (index >= self.size):
a = [:foo, 'bar', 2] a.insert(5, :bat, :bam) a # => [:foo, "bar", 2, nil, nil, :bat, :bam]
Does nothing if no objects given:
a = [:foo, 'bar', 2] a.insert(1) a.insert(50) a.insert(-50) a # => [:foo, "bar", 2]
When index is negative, inserts all given objects after the element at offset index+self.size:
a = [:foo, 'bar', 2] a.insert(-2, :bat, :bam) a # => [:foo, "bar", :bat, :bam, 2]
Returns the count of elements in self.
Returns the index of a specified element.
When argument object is given but no block, returns the index of the first element element for which object == element:
a = [:foo, 'bar', 2, 'bar'] a.index('bar') # => 1
Returns nil if no such element found.
When both argument object and a block are given, calls the block with each successive element; returns the index of the first element for which the block returns a truthy value:
a = [:foo, 'bar', 2, 'bar'] a.index {|element| element == 'bar' } # => 1
Returns nil if the block never returns a truthy value.
When neither an argument nor a block is given, returns a new Enumerator:
a = [:foo, 'bar', 2] e = a.index e # => #<Enumerator: [:foo, "bar", 2]:index> e.each {|element| element == 'bar' } # => 1
Related: rindex.
Returns the new String formed by joining the array elements after conversion. For each element element:
Uses element.to_s if element is not a kind_of?(Array).
Uses recursive element.join(separator) if element is a kind_of?(Array).
With no argument, joins using the output field separator, $,:
a = [:foo, 'bar', 2] $, # => nil a.join # => "foobar2"
With string argument separator, joins using that separator:
a = [:foo, 'bar', 2] a.join("\n") # => "foo\nbar\n2"
Joins recursively for nested Arrays:
a = [:foo, [:bar, [:baz, :bat]]] a.join # => "foobarbazbat"
Transposes the rows and columns in an Array of Arrays; the nested Arrays must all be the same size:
a = [[:a0, :a1], [:b0, :b1], [:c0, :c1]] a.transpose # => [[:a0, :b0, :c0], [:a1, :b1, :c1]]
Returns true if for some index i in self, obj == self[i]; otherwise false:
[0, 1, 2].include?(2) # => true [0, 1, 2].include?(3) # => false
Returns one of the following:
The minimum-valued element from self.
A new Array of minimum-valued elements selected from self.
When no block is given, each element in self must respond to method <=> with an Integer.
With no argument and no block, returns the element in self having the minimum value per method <=>:
[0, 1, 2].min # => 0
With Integer argument n and no block, returns a new Array with at most n elements, in ascending order per method <=>:
[0, 1, 2, 3].min(3) # => [0, 1, 2] [0, 1, 2, 3].min(6) # => [0, 1, 2, 3]
When a block is given, the block must return an Integer.
With a block and no argument, calls the block self.size-1 times to compare elements; returns the element having the minimum value per the block:
['0', '00', '000'].min { |a, b| a.size <=> b.size } # => "0"
With an argument n and a block, returns a new Array with at most n elements, in ascending order per the block:
['0', '00', '000'].min(2) {|a, b| a.size <=> b.size } # => ["0", "00"]
Returns a new 2-element Array containing the minimum and maximum values from self, either per method <=> or per a given block:.
When no block is given, each element in self must respond to method <=> with an Integer; returns a new 2-element Array containing the minimum and maximum values from self, per method <=>:
[0, 1, 2].minmax # => [0, 2]
When a block is given, the block must return an Integer; the block is called self.size-1 times to compare elements; returns a new 2-element Array containing the minimum and maximum values from self, per the block:
['0', '00', '000'].minmax {|a, b| a.size <=> b.size } # => ["0", "000"]
Calls the block, if given, with combinations of elements of self; returns self. The order of combinations is indeterminate.
When a block and an in-range positive Integer argument n (0 < n <= self.size) are given, calls the block with all n-tuple combinations of self.
Example:
a = [0, 1, 2] a.combination(2) {|combination| p combination }
Output:
[0, 1] [0, 2] [1, 2]
Another example:
a = [0, 1, 2] a.combination(3) {|combination| p combination }
Output:
[0, 1, 2]
When n is zero, calls the block once with a new empty Array:
a = [0, 1, 2] a1 = a.combination(0) {|combination| p combination }
Output:
[]
When n is out of range (negative or larger than self.size), does not call the block:
a = [0, 1, 2] a.combination(-1) {|combination| fail 'Cannot happen' } a.combination(4) {|combination| fail 'Cannot happen' }
Returns a new Enumerator if no block given:
a = [0, 1, 2] a.combination(2) # => #<Enumerator: [0, 1, 2]:combination(2)>
Returns elements from self; does not modify self.
When no argument is given, returns the first element:
a = [:foo, 'bar', 2] a.first # => :foo a # => [:foo, "bar", 2]
If self is empty, returns nil.
When non-negative Integer argument n is given, returns the first n elements in a new Array:
a = [:foo, 'bar', 2] a.first(2) # => [:foo, "bar"]
If n >= array.size, returns all elements:
a = [:foo, 'bar', 2] a.first(50) # => [:foo, "bar", 2]
If n == 0 returns an new empty Array:
a = [:foo, 'bar', 2] a.first(0) # []
Related: last.
Returns elements from self; self is not modified.
When no argument is given, returns the last element:
a = [:foo, 'bar', 2] a.last # => 2 a # => [:foo, "bar", 2]
If self is empty, returns nil.
When non-negative Integer argument n is given, returns the last n elements in a new Array:
a = [:foo, 'bar', 2] a.last(2) # => ["bar", 2]
If n >= array.size, returns all elements:
a = [:foo, 'bar', 2] a.last(50) # => [:foo, "bar", 2]
If n == 0, returns an new empty Array:
a = [:foo, 'bar', 2] a.last(0) # []
Related: first.
Builds a command line string from an argument list array joining all elements escaped for the Bourne shell and separated by a space.
See Shellwords.shelljoin for details.
Returns a Hash containing implementation-dependent counters inside the VM.
This hash includes information about method/constant caches:
{
:constant_cache_invalidations=>2,
:constant_cache_misses=>14,
:global_cvar_state=>27
}
If USE_DEBUG_COUNTER is enabled, debug counters will be included.
The contents of the hash are implementation specific and may be changed in the future.
This method is only expected to work on C Ruby.
Returns self truncated (toward zero) to a precision of ndigits decimal digits.
When ndigits is negative, the returned value has at least ndigits.abs trailing zeros:
555.truncate(-1) # => 550 555.truncate(-2) # => 500 -555.truncate(-2) # => -500
Returns self when ndigits is zero or positive.
555.truncate # => 555 555.truncate(50) # => 555
Related: Integer#round.
Returns the remainder after dividing self by other.
Examples:
11.remainder(4) # => 3 11.remainder(-4) # => 3 -11.remainder(4) # => -3 -11.remainder(-4) # => -3 12.remainder(4) # => 0 12.remainder(-4) # => 0 -12.remainder(4) # => 0 -12.remainder(-4) # => 0 13.remainder(4.0) # => 1.0 13.remainder(Rational(4, 1)) # => (1/1)
Returns a string containing the place-value representation of self in radix base (in 2..36).
12345.to_s # => "12345" 12345.to_s(2) # => "11000000111001" 12345.to_s(8) # => "30071" 12345.to_s(10) # => "12345" 12345.to_s(16) # => "3039" 12345.to_s(36) # => "9ix" 78546939656932.to_s(36) # => "rubyrules"
Raises an exception if base is out of range.
Since self is already an Integer, always returns true.
Returns 1.