Returns a hash of the name/value pairs, to use in pattern matching.
Measure = Data.define(:amount, :unit) distance = Measure[10, 'km'] distance.deconstruct_keys(nil) #=> {:amount=>10, :unit=>"km"} distance.deconstruct_keys([:amount]) #=> {:amount=>10} # usage case distance in amount:, unit: 'km' # calls #deconstruct_keys underneath puts "It is #{amount} kilometers away" else puts "Don't know how to handle it" end # prints "It is 10 kilometers away"
Or, with checking the class, too:
case distance in Measure(amount:, unit: 'km') puts "It is #{amount} kilometers away" # ... end
Returns a hash of the named captures for the given names.
m = /(?<hours>\d{2}):(?<minutes>\d{2}):(?<seconds>\d{2})/.match("18:37:22") m.deconstruct_keys([:hours, :minutes]) # => {:hours => "18", :minutes => "37"} m.deconstruct_keys(nil) # => {:hours => "18", :minutes => "37", :seconds => "22"}
Returns an empty hash of no named captures were defined:
m = /(\d{2}):(\d{2}):(\d{2})/.match("18:37:22") m.deconstruct_keys(nil) # => {}
Ruby expects the dylib to follow a file name convention for loading
Returns an File instance opened console.
If sym is given, it will be sent to the opened console with args and the result will be returned instead of the console IO itself.
You must require ‘io/console’ to use this method.
Returns system configuration variable using confstr().
name should be a constant under Etc which begins with CS_.
The return value is a string or nil. nil means no configuration-defined value. (confstr() returns 0 but errno is not set.)
Etc.confstr(Etc::CS_PATH) #=> "/bin:/usr/bin" # GNU/Linux Etc.confstr(Etc::CS_GNU_LIBC_VERSION) #=> "glibc 2.18" Etc.confstr(Etc::CS_GNU_LIBPTHREAD_VERSION) #=> "NPTL 2.18"
The standard configuration object for gems.
Use the given configuration object (which implements the ConfigFile protocol) as the standard configuration object.
The logical inverse of ‘capture_last_end_same_indent`
When there is an invalid block with an ‘end` missing a keyword right after another `end`, it is unclear where which end is missing the keyword.
Take this example:
class Dog # 1
puts "woof" # 2
end # 3
end # 4
the problem line will be identified as:
> end # 4
This happens because lines 1, 2, and 3 are technically valid code and are expanded first, deemed valid, and hidden. We need to un-hide the matching keyword on line 1. Also work backwards and if there’s a mis-matched end, show it too
Iterates over strongly connected component in the subgraph reachable from node.
Return value is unspecified.
each_strongly_connected_component_from doesn’t call tsort_each_node.
class G include TSort def initialize(g) @g = g end def tsort_each_child(n, &b) @g[n].each(&b) end def tsort_each_node(&b) @g.each_key(&b) end end graph = G.new({1=>[2, 3], 2=>[4], 3=>[2, 4], 4=>[]}) graph.each_strongly_connected_component_from(2) {|scc| p scc } #=> [4] # [2] graph = G.new({1=>[2], 2=>[3, 4], 3=>[2], 4=>[]}) graph.each_strongly_connected_component_from(2) {|scc| p scc } #=> [4] # [2, 3]
Iterates over strongly connected components in a graph. The graph is represented by node and each_child.
node is the first node. each_child should have call method which takes a node argument and yields for each child node.
Return value is unspecified.
TSort.each_strongly_connected_component_from is a class method and it doesn’t need a class to represent a graph which includes TSort.
graph = {1=>[2], 2=>[3, 4], 3=>[2], 4=>[]} each_child = lambda {|n, &b| graph[n].each(&b) } TSort.each_strongly_connected_component_from(1, each_child) {|scc| p scc } #=> [4] # [2, 3] # [1]
Returns the new Array suitable for pattern matching containing the values of the row.
Set the default id conversion object.
This is expected to be an instance such as DRb::DRbIdConv that responds to to_id and to_obj that can convert objects to and from DRb references.
See DRbServer#default_id_conv.
Set the default id conversion object.
This is expected to be an instance such as DRb::DRbIdConv that responds to to_id and to_obj that can convert objects to and from DRb references.
See DRbServer#default_id_conv.
Returns the fractional part of the second in range (Rational(0, 1)…Rational(1, 1)):
DateTime.new(2001, 2, 3, 4, 5, 6.5).sec_fraction # => (1/2)
Date#second_fraction is an alias for Date#sec_fraction.
Requests a connection to be made on the given remote_sockaddr after O_NONBLOCK is set for the underlying file descriptor. Returns 0 if successful, otherwise an exception is raised.
# +remote_sockaddr+ - the +struct+ sockaddr contained in a string or Addrinfo object
# Pull down Google's web page require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(80, 'www.google.com') begin # emulate blocking connect socket.connect_nonblock(sockaddr) rescue IO::WaitWritable IO.select(nil, [socket]) # wait 3-way handshake completion begin socket.connect_nonblock(sockaddr) # check connection failure rescue Errno::EISCONN end end socket.write("GET / HTTP/1.0\r\n\r\n") results = socket.read
Refer to Socket#connect for the exceptions that may be thrown if the call to connect_nonblock fails.
Socket#connect_nonblock may raise any error corresponding to connect(2) failure, including Errno::EINPROGRESS.
If the exception is Errno::EINPROGRESS, it is extended by IO::WaitWritable. So IO::WaitWritable can be used to rescue the exceptions for retrying connect_nonblock.
By specifying a keyword argument exception to false, you can indicate that connect_nonblock should not raise an IO::WaitWritable exception, but return the symbol :wait_writable instead.
# Socket#connect
Compiled instruction sequence represented by a RubyVM::InstructionSequence instance on the :script_compiled event.
Note that this method is MRI specific.
Returns an array of flattened objects returned by the block.
With a block given, calls the block with successive elements; returns a flattened array of objects returned by the block:
[0, 1, 2, 3].flat_map {|element| -element } # => [0, -1, -2, -3] [0, 1, 2, 3].flat_map {|element| [element, -element] } # => [0, 0, 1, -1, 2, -2, 3, -3] [[0, 1], [2, 3]].flat_map {|e| e + [100] } # => [0, 1, 100, 2, 3, 100] {foo: 0, bar: 1, baz: 2}.flat_map {|key, value| [key, value] } # => [:foo, 0, :bar, 1, :baz, 2]
With no block given, returns an Enumerator.
Alias: collect_concat.
Calls the block with each successive overlapped n-tuple of elements; returns self:
a = [] (1..5).each_cons(3) {|element| a.push(element) } a # => [[1, 2, 3], [2, 3, 4], [3, 4, 5]] a = [] h = {foo: 0, bar: 1, baz: 2, bam: 3} h.each_cons(2) {|element| a.push(element) } a # => [[[:foo, 0], [:bar, 1]], [[:bar, 1], [:baz, 2]], [[:baz, 2], [:bam, 3]]]
With no block given, returns an Enumerator.
Adds a post-install hook that will be passed an Gem::Installer instance when Gem::Installer#install is called
Adds a post-installs hook that will be passed a Gem::DependencyInstaller and a list of installed specifications when Gem::DependencyInstaller#install is complete
Adds a post-uninstall hook that will be passed a Gem::Uninstaller instance and the spec that was uninstalled when Gem::Uninstaller#uninstall is called
Returns the new Hash suitable for pattern matching containing only the keys specified as an argument.