Returns a new String containing the hash entries:
h = {foo: 0, bar: 1, baz: 2} h.inspect # => "{foo: 0, bar: 1, baz: 2}"
Returns a copy of +self+ with all +nil+-valued entries removed:
h = {foo: 0, bar: nil, baz: 2, bat: nil}
h.compact # => {foo: 0, baz: 2}
Related: see Methods for Deleting.
Returns self with all its nil-valued entries removed (in place):
h = {foo: 0, bar: nil, baz: 2, bat: nil} h.compact! # => {foo: 0, baz: 2}
Returns nil if no entries were removed.
Returns the contents of the environment as a String:
ENV.replace('foo' => '0', 'bar' => '1') ENV.inspect # => "{\"bar\"=>\"1\", \"foo\"=>\"0\"}"
Raises TypeError, because ENV is a wrapper for the process-wide environment variables and a clone is useless. Use to_h to get a copy of ENV data as a hash.
Returns “ARGF”.
Sets optional filename and line number that will be used in ERB code evaluation and error reporting. See also filename= and lineno=
erb = ERB.new('<%= some_x %>') erb.render # undefined local variable or method `some_x' # from (erb):1 erb.location = ['file.erb', 3] # All subsequent error reporting would use new location erb.render # undefined local variable or method `some_x' # from file.erb:4
Returns a network byte ordered string form of the IP address.
Returns a string containing a human-readable representation of the ipaddr. (“#<IPAddr: family:address/mask>”)
Creates an option from the given parameters params. See Parameters for New Options.
The block, if given, is the handler for the created option. When the option is encountered during command-line parsing, the block is called with the argument given for the option, if any. See Option Handlers.
Parses environment variable env or its uppercase with splitting like a shell.
env defaults to the basename of the program.
Returns a string representation of self:
Measure = Data.define(:amount, :unit) distance = Measure[10, 'km'] p distance # uses #inspect underneath #<data Measure amount=10, unit="km"> puts distance # uses #to_s underneath, same representation #<data Measure amount=10, unit="km">
Returns a string representation of self:
m = /.$/.match("foo") # => #<MatchData "o"> m.inspect # => "#<MatchData \"o\">" m = /(.)(.)(.)/.match("foo") # => #<MatchData "foo" 1:"f" 2:"o" 3:"o"> m.inspect # => "#<MatchData \"foo\" 1:\"f\" 2:\"o\ m = /(.)(.)?(.)/.match("fo") # => #<MatchData "fo" 1:"f" 2:nil 3:"o"> m.inspect # => "#<MatchData \"fo\" 1:\"f\" 2:nil 3:\"o\">"
Related: MatchData#to_s.
Returns the target string if it was frozen; otherwise, returns a frozen copy of the target string:
m = /(.)(.)(\d+)(\d)/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8"> m.string # => "THX1138."
Increases left margin after newline with indent for line breaks added in the block.
The string representation of false is “false”.
Returns the unique identifier for this proc, along with an indication of where the proc was defined.
Returns a clone of this method.
class A def foo return "bar" end end m = A.new.method(:foo) m.call # => "bar" n = m.clone.call # => "bar"
Returns a human-readable description of the underlying method.
"cat".method(:count).inspect #=> "#<Method: String#count(*)>" (1..3).method(:map).inspect #=> "#<Method: Range(Enumerable)#map()>"
In the latter case, the method description includes the “owner” of the original method (Enumerable module, which is included into Range).
inspect also provides, when possible, method argument names (call sequence) and source location.
require 'net/http' Net::HTTP.method(:get).inspect #=> "#<Method: Net::HTTP.get(uri_or_host, path=..., port=...) <skip>/lib/ruby/2.7.0/net/http.rb:457>"
... in argument definition means argument is optional (has some default value).
For methods defined in C (language core and extensions), location and argument names can’t be extracted, and only generic information is provided in form of * (any number of arguments) or _ (some positional argument).
"cat".method(:count).inspect #=> "#<Method: String#count(*)>" "cat".method(:+).inspect #=> "#<Method: String#+(_)>""
Returns a clone of this method.
class A def foo return "bar" end end m = A.new.method(:foo) m.call # => "bar" n = m.clone.call # => "bar"
Returns a human-readable description of the underlying method.
"cat".method(:count).inspect #=> "#<Method: String#count(*)>" (1..3).method(:map).inspect #=> "#<Method: Range(Enumerable)#map()>"
In the latter case, the method description includes the “owner” of the original method (Enumerable module, which is included into Range).
inspect also provides, when possible, method argument names (call sequence) and source location.
require 'net/http' Net::HTTP.method(:get).inspect #=> "#<Method: Net::HTTP.get(uri_or_host, path=..., port=...) <skip>/lib/ruby/2.7.0/net/http.rb:457>"
... in argument definition means argument is optional (has some default value).
For methods defined in C (language core and extensions), location and argument names can’t be extracted, and only generic information is provided in form of * (any number of arguments) or _ (some positional argument).
"cat".method(:count).inspect #=> "#<Method: String#count(*)>" "cat".method(:+).inspect #=> "#<Method: String#+(_)>""
Returns the number of Ractors currently running or blocking (waiting).
Ractor.count #=> 1 r = Ractor.new(name: 'example') { Ractor.yield(1) } Ractor.count #=> 2 (main + example ractor) r.take # wait for Ractor.yield(1) r.take # wait until r will finish Ractor.count #=> 1
Returns an array of all existing Thread objects that belong to this group.
ThreadGroup::Default.list #=> [#<Thread:0x401bdf4c run>]