Returns the array of captures; equivalent to mtch.to_a[1..-1].
f1,f2,f3,f4 = /(.)(.)(\d+)(\d)/.match("THX1138.").captures f1 #=> "H" f2 #=> "X" f3 #=> "113" f4 #=> "8"
This says “you can break a line here if necessary”, and a width-column text sep is inserted if a line is not broken at the point.
If sep is not specified, “ ” is used.
If width is not specified, sep.length is used. You will have to specify this when sep is a multibyte character, for example.
Looks up the first IP address for name.
Looks up all IP address for name.
Looks up the first IP address for name.
Looks up all IP address for name.
Returns true if the set contains no elements.
Replaces the contents of the set with the contents of the given enumerable object and returns self.
set = Set[1, 'c', :s] #=> #<Set: {1, "c", :s}> set.replace([1, 2]) #=> #<Set: {1, 2}> set #=> #<Set: {1, 2}>
Equivalent to Set#delete_if, but returns nil if no changes were made. Returns an enumerator if no block is given.
Resets the internal state after modification to existing elements and returns self.
Elements will be reindexed and deduplicated.
Creates a temporary file as usual File object (not Tempfile). It doesn’t use finalizer and delegation.
If no block is given, this is similar to Tempfile.new except creating File instead of Tempfile. The created file is not removed automatically. You should use File.unlink to remove it.
If a block is given, then a File object will be constructed, and the block is invoked with the object as the argument. The File object will be automatically closed and the temporary file is removed after the block terminates. The call returns the value of the block.
In any case, all arguments (basename, tmpdir, mode, and **options) will be treated as Tempfile.new.
Tempfile.create('foo', '/home/temp') do |f| # ... do something with f ... end
Returns true if there are no threads in the pool still running.
Returns true if there are no threads in the pool still running.
Wraps the block in a single, VM-global Mutex.synchronize, returning the value of the block. A thread executing inside the exclusive section will only block other threads which also use the Thread.exclusive mechanism.
Returns true if thr is running or sleeping.
thr = Thread.new { } thr.join #=> #<Thread:0x401b3fb0 dead> Thread.current.alive? #=> true thr.alive? #=> false
Returns true if the queue is empty.
Returns true if the queue is empty.
Equivalent to Kernel::gets, except readline raises EOFError at end of file.
Returns an array containing the lines returned by calling Kernel.gets(sep) until the end of file.
Use Kernel#gem to activate a specific version of gem_name.
requirements is a list of version requirements that the specified gem must match, most commonly “= example.version.number”. See Gem::Requirement for how to specify a version requirement.
If you will be activating the latest version of a gem, there is no need to call Kernel#gem, Kernel#require will do the right thing for you.
Kernel#gem returns true if the gem was activated, otherwise false. If the gem could not be found, didn’t match the version requirements, or a different version was already activated, an exception will be raised.
Kernel#gem should be called before any require statements (otherwise RubyGems may load a conflicting library version).
Kernel#gem only loads prerelease versions when prerelease requirements are given:
gem 'rake', '>= 1.1.a', '< 2'
In older RubyGems versions, the environment variable GEM_SKIP could be used to skip activation of specified gems, for example to test out changes that haven’t been installed yet. Now RubyGems defers to -I and the RUBYLIB environment variable to skip activation of a gem.
Example:
GEM_SKIP=libA:libB ruby -I../libA -I../libB ./mycode.rb
Returns an array of every element in enum for which Pattern === element. If the optional block is supplied, each matching element is passed to it, and the block’s result is stored in the output array.
(1..100).grep 38..44 #=> [38, 39, 40, 41, 42, 43, 44] c = IO.constants c.grep(/SEEK/) #=> [:SEEK_SET, :SEEK_CUR, :SEEK_END] res = c.grep(/SEEK/) { |v| IO.const_get(v) } res #=> [0, 1, 2]