Build a single index for RubyGems 1.2 and newer
Builds indices for RubyGems 1.2 and newer. Handles full, latest, prerelease
The location of the default spec file for default gems.
Returns the count of elements in self.
Removes zero or more elements from self; returns self.
When no block is given, removes from self each element ele such that ele == obj; returns the last deleted element:
s1 = 'bar'; s2 = 'bar' a = [:foo, s1, 2, s2] a.delete('bar') # => "bar" a # => [:foo, 2]
Returns nil if no elements removed.
When a block is given, removes from self each element ele such that ele == obj.
If any such elements are found, ignores the block and returns the last deleted element:
s1 = 'bar'; s2 = 'bar' a = [:foo, s1, 2, s2] deleted_obj = a.delete('bar') {|obj| fail 'Cannot happen' } a # => [:foo, 2]
If no such elements are found, returns the block’s return value:
a = [:foo, 'bar', 2] a.delete(:nosuch) {|obj| "#{obj} not found" } # => "nosuch not found"
When called with positive Integer argument count and a block, calls the block with each element, then does so again, until it has done so count times; returns nil:
output = [] [0, 1].cycle(2) {|element| output.push(element) } # => nil output # => [0, 1, 0, 1]
If count is zero or negative, does not call the block:
[0, 1].cycle(0) {|element| fail 'Cannot happen' } # => nil [0, 1].cycle(-1) {|element| fail 'Cannot happen' } # => nil
When a block is given, and argument is omitted or nil, cycles forever:
# Prints 0 and 1 forever. [0, 1].cycle {|element| puts element } [0, 1].cycle(nil) {|element| puts element }
When no block is given, returns a new Enumerator:
[0, 1].cycle(2) # => #<Enumerator: [0, 1]:cycle(2)> [0, 1].cycle # => # => #<Enumerator: [0, 1]:cycle> [0, 1].cycle.first(5) # => [0, 1, 0, 1, 0]
Shuffles the elements of self in place.
a = [1, 2, 3] #=> [1, 2, 3] a.shuffle! #=> [2, 3, 1] a #=> [2, 3, 1]
The optional random argument will be used as the random number generator:
a.shuffle!(random: Random.new(1)) #=> [1, 3, 2]
Returns a new array with elements of self shuffled.
a = [1, 2, 3] #=> [1, 2, 3] a.shuffle #=> [2, 3, 1] a #=> [1, 2, 3]
The optional random argument will be used as the random number generator:
a.shuffle(random: Random.new(1)) #=> [1, 3, 2]
Returns random elements from self.
When no arguments are given, returns a random element from self:
a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] a.sample # => 3 a.sample # => 8
If self is empty, returns nil.
When argument n is given, returns a new Array containing n random elements from self:
a.sample(3) # => [8, 9, 2] a.sample(6) # => [9, 6, 10, 3, 1, 4]
Returns no more than a.size elements (because no new duplicates are introduced):
a.sample(a.size * 2) # => [6, 4, 1, 8, 5, 9, 10, 2, 3, 7]
But self may contain duplicates:
a = [1, 1, 1, 2, 2, 3] a.sample(a.size * 2) # => [1, 1, 3, 2, 1, 2]
Returns a new empty Array if self is empty.
The optional random argument will be used as the random number generator:
a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] a.sample(random: Random.new(1)) #=> 6 a.sample(4, random: Random.new(1)) #=> [6, 10, 9, 2]
The primary interface to this library. Use to setup delegation when defining your class.
class MyClass < DelegateClass(ClassToDelegateTo) # Step 1 def initialize super(obj_of_ClassToDelegateTo) # Step 2 end end
or:
MyClass = DelegateClass(ClassToDelegateTo) do # Step 1 def initialize super(obj_of_ClassToDelegateTo) # Step 2 end end
Here’s a sample of use from Tempfile which is really a File object with a few special rules about storage location and when the File should be deleted. That makes for an almost textbook perfect example of how to use delegation.
class Tempfile < DelegateClass(File) # constant and class member data initialization... def initialize(basename, tmpdir=Dir::tmpdir) # build up file path/name in var tmpname... @tmpfile = File.open(tmpname, File::RDWR|File::CREAT|File::EXCL, 0600) # ... super(@tmpfile) # below this point, all methods of File are supported... end # ... end
Produces a shallow copy of obj—the instance variables of obj are copied, but not the objects they reference.
This method may have class-specific behavior. If so, that behavior will be documented under the #initialize_copy method of the class.
In general, clone and dup may have different semantics in descendant classes. While clone is used to duplicate an object, including its internal state, dup typically uses the class of the descendant object to create the new instance.
When using dup, any modules that the object has been extended with will not be copied.
class Klass attr_accessor :str end module Foo def foo; 'foo'; end end s1 = Klass.new #=> #<Klass:0x401b3a38> s1.extend(Foo) #=> #<Klass:0x401b3a38> s1.foo #=> "foo" s2 = s1.clone #=> #<Klass:0x401be280> s2.foo #=> "foo" s3 = s1.dup #=> #<Klass:0x401c1084> s3.foo #=> NoMethodError: undefined method `foo' for #<Klass:0x401c1084>
Returns a list of the names of public and protected methods of obj. This will include all the methods accessible in obj’s ancestors. If the optional parameter is false, it returns an array of obj’s public and protected singleton methods, the array will not include methods in modules included in obj.
class Klass def klass_method() end end k = Klass.new k.methods[0..9] #=> [:klass_method, :nil?, :===, # :==~, :!, :eql? # :hash, :<=>, :class, :singleton_class] k.methods.length #=> 56 k.methods(false) #=> [] def k.singleton_method; end k.methods(false) #=> [:singleton_method] module M123; def m123; end end k.extend M123 k.methods(false) #=> [:singleton_method]
Looks up the named method as a receiver in obj, returning a Method object (or raising NameError). The Method object acts as a closure in obj’s object instance, so instance variables and the value of self remain available.
class Demo def initialize(n) @iv = n end def hello() "Hello, @iv = #{@iv}" end end k = Demo.new(99) m = k.method(:hello) m.call #=> "Hello, @iv = 99" l = Demo.new('Fred') m = l.method("hello") m.call #=> "Hello, @iv = Fred"
Note that Method implements to_proc method, which means it can be used with iterators.
[ 1, 2, 3 ].each(&method(:puts)) # => prints 3 lines to stdout out = File.open('test.txt', 'w') [ 1, 2, 3 ].each(&out.method(:puts)) # => prints 3 lines to file require 'date' %w[2017-03-01 2017-03-02].collect(&Date.method(:parse)) #=> [#<Date: 2017-03-01 ((2457814j,0s,0n),+0s,2299161j)>, #<Date: 2017-03-02 ((2457815j,0s,0n),+0s,2299161j)>]
Returns true if int is an odd number.
Returns the angle part of its polar form.
Complex.polar(3, Math::PI/2).arg #=> 1.5707963267948966
Returns 0 if the value is positive, pi otherwise.
Returns the receiver.
Convert self to locale encoding
Escapes str so that it can be safely used in a Bourne shell command line.
See Shellwords.shellescape for details.
Returns the count of characters (not bytes) in self:
"\x80\u3042".length # => 2 "hello".length # => 5
String#size is an alias for String#length.
Related: String#bytesize.
Returns a quoted version of the string with all non-printing characters replaced by \xHH notation and all special characters escaped.
This method can be used for round-trip: if the resulting new_str is eval’ed, it will produce the original string.
"hello \n ''".dump #=> "\"hello \\n ''\"" "\f\x00\xff\\\"".dump #=> "\"\\f\\x00\\xFF\\\\\\\"\""
See also String#undump.