Terminates option parsing. Optional parameter arg
is a string pushed back to be the first non-option argument.
Add separator in summary.
Returns the matched substring corresponding to the given argument.
When non-negative argument n
is given, returns the matched substring for the n
th match:
m = /(.)(.)(\d+)(\d)(\w)?/.match("THX1138.") # => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8" 5:nil> m.match(0) # => "HX1138" m.match(4) # => "8" m.match(5) # => nil
When string or symbol argument name
is given, returns the matched substring for the given name:
m = /(?<foo>.)(.)(?<bar>.+)/.match("hoge") # => #<MatchData "hoge" foo:"h" bar:"ge"> m.match('foo') # => "h" m.match(:bar) # => "ge"
This is a convenience method which is same as follows:
begin q = PrettyPrint.new(output, maxwidth, newline, &genspace) ... q.flush output end
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 the full path name of the temporary file. This will be nil if unlink
has been called.
Creates a file in the underlying file system; returns a new File object based on that file.
With no block given and no arguments, creates and returns file whose:
Directory is the system temporary directory (system-dependent).
Generated filename is unique in that directory.
Permissions are 0600
; see File Permissions.
Mode is 'w+'
(read/write mode, positioned at the end).
The temporary file removal depends on the keyword argument anonymous
and whether a block is given or not. See the description about the anonymous
keyword argument later.
Example:
f = Tempfile.create # => #<File:/tmp/20220505-9795-17ky6f6> f.class # => File f.path # => "/tmp/20220505-9795-17ky6f6" f.stat.mode.to_s(8) # => "100600" f.close File.exist?(f.path) # => true File.unlink(f.path) File.exist?(f.path) # => false Tempfile.create {|f| f.puts "foo" f.rewind f.read # => "foo\n" f.path # => "/tmp/20240524-380207-oma0ny" File.exist?(f.path) # => true } # The file is removed at block exit. f = Tempfile.create(anonymous: true) # The file is already removed because anonymous f.path # => "/tmp/" (no filename since no file) f.puts "foo" f.rewind f.read # => "foo\n" f.close Tempfile.create(anonymous: true) {|f| # The file is already removed because anonymous f.path # => "/tmp/" (no filename since no file) f.puts "foo" f.rewind f.read # => "foo\n" }
The argument basename
, if given, may be one of the following:
A string: the generated filename begins with basename
:
Tempfile.create('foo') # => #<File:/tmp/foo20220505-9795-1gok8l9>
An array of two strings [prefix, suffix]
: the generated filename begins with prefix
and ends with suffix
:
Tempfile.create(%w/foo .jpg/) # => #<File:/tmp/foo20220505-17839-tnjchh.jpg>
With arguments basename
and tmpdir
, the file is created in the directory tmpdir
:
Tempfile.create('foo', '.') # => #<File:./foo20220505-9795-1emu6g8>
Keyword arguments mode
and options
are passed directly to the method File.open
:
The value given for mode
must be an integer and may be expressed as the logical OR of constants defined in File::Constants
.
For options
, see Open Options.
The keyword argument anonymous
specifies when the file is removed.
anonymous=false
(default) without a block: the file is not removed.
anonymous=false
(default) with a block: the file is removed after the block exits.
anonymous=true
without a block: the file is removed before returning.
anonymous=true
with a block: the file is removed before the block is called.
In the first case (anonymous=false
without a block), the file is not removed automatically. It should be explicitly closed. It can be used to rename to the desired filename. If the file is not needed, it should be explicitly removed.
The File#path
method of the created file object returns the temporary directory with a trailing slash when anonymous
is true.
When a block is given, it creates the file as described above, passes it to the block, and returns the block’s value. Before the returning, the file object is closed and the underlying file is removed:
Tempfile.create {|file| file.path } # => "/tmp/20220505-9795-rkists"
Implementation note:
The keyword argument +anonymous=true+ is implemented using FILE_SHARE_DELETE on Windows. O_TMPFILE is used on Linux.
Related: Tempfile.new
.
Returns true
if a Proc
object is lambda. false
if non-lambda.
The lambda-ness affects argument handling and the behavior of return
and break
.
A Proc
object generated by proc
ignores extra arguments.
proc {|a,b| [a,b] }.call(1,2,3) #=> [1,2]
It provides nil
for missing arguments.
proc {|a,b| [a,b] }.call(1) #=> [1,nil]
It expands a single array argument.
proc {|a,b| [a,b] }.call([1,2]) #=> [1,2]
A Proc
object generated by lambda
doesn’t have such tricks.
lambda {|a,b| [a,b] }.call(1,2,3) #=> ArgumentError lambda {|a,b| [a,b] }.call(1) #=> ArgumentError lambda {|a,b| [a,b] }.call([1,2]) #=> ArgumentError
Proc#lambda?
is a predicate for the tricks. It returns true
if no tricks apply.
lambda {}.lambda? #=> true proc {}.lambda? #=> false
Proc.new
is the same as proc
.
Proc.new {}.lambda? #=> false
lambda
, proc
and Proc.new
preserve the tricks of a Proc
object given by &
argument.
lambda(&lambda {}).lambda? #=> true proc(&lambda {}).lambda? #=> true Proc.new(&lambda {}).lambda? #=> true lambda(&proc {}).lambda? #=> false proc(&proc {}).lambda? #=> false Proc.new(&proc {}).lambda? #=> false
A Proc
object generated by &
argument has the tricks
def n(&b) b.lambda? end n {} #=> false
The &
argument preserves the tricks if a Proc
object is given by &
argument.
n(&lambda {}) #=> true n(&proc {}) #=> false n(&Proc.new {}) #=> false
A Proc
object converted from a method has no tricks.
def m() end method(:m).to_proc.lambda? #=> true n(&method(:m)) #=> true n(&method(:m).to_proc) #=> true
define_method
is treated the same as method definition. The defined method has no tricks.
class C define_method(:d) {} end C.new.d(1,2) #=> ArgumentError C.new.method(:d).to_proc.lambda? #=> true
define_method
always defines a method without the tricks, even if a non-lambda Proc
object is given. This is the only exception for which the tricks are not preserved.
class C define_method(:e, &proc {}) end C.new.e(1,2) #=> ArgumentError C.new.method(:e).to_proc.lambda? #=> true
This exception ensures that methods never have tricks and makes it easy to have wrappers to define methods that behave as usual.
class C def self.def2(name, &body) define_method(name, &body) end def2(:f) {} end C.new.f(1,2) #=> ArgumentError
The wrapper def2 defines a method which has no tricks.
Get a message from the ractor’s outgoing port, which was put there by Ractor.yield
or at ractor’s termination.
r = Ractor.new do Ractor.yield 'explicit yield' 'last value' end puts r.take #=> 'explicit yield' puts r.take #=> 'last value' puts r.take # Ractor::ClosedError (The outgoing-port is already closed)
The fact that the last value is also sent to the outgoing port means that take
can be used as an analog of Thread#join
(“just wait until ractor finishes”). However, it will raise if somebody has already consumed that message.
If the outgoing port was closed with close_outgoing
, the method will raise Ractor::ClosedError
.
r = Ractor.new do sleep(500) Ractor.yield 'Hello from ractor' end r.close_outgoing r.take # Ractor::ClosedError (The outgoing-port is already closed) # The error would be raised immediately, not when ractor will try to receive
If an uncaught exception is raised in the Ractor
, it is propagated by take as a Ractor::RemoteError
.
r = Ractor.new {raise "Something weird happened"} begin r.take rescue => e p e # => #<Ractor::RemoteError: thrown by remote Ractor.> p e.ractor == r # => true p e.cause # => #<RuntimeError: Something weird happened> end
Ractor::ClosedError
is a descendant of StopIteration
, so the termination of the ractor will break out of any loops that receive this message without propagating the error:
r = Ractor.new do 3.times {|i| Ractor.yield "message #{i}"} "finishing" end loop {puts "Received: " + r.take} puts "Continue successfully"
This will print:
Received: message 0 Received: message 1 Received: message 2 Received: finishing Continue successfully
Basically the same as ::new
. However, if class Thread
is subclassed, then calling start
in that subclass will not invoke the subclass’s initialize
method.
Terminates thr
and schedules another thread to be run, returning the terminated Thread
. If this is the main thread, or the last thread, exits the process.
Path of the file being run
Return the tag object which was called for.
Creates a new Pathname
object from the given string, path
, and returns pathname object.
In order to use this constructor, you must first require the Pathname
standard library extension.
require 'pathname' Pathname("/home/zzak") #=> #<Pathname:/home/zzak>
See also Pathname::new
for more information.
Yields self to the block, and then returns self. The primary purpose of this method is to “tap into” a method chain, in order to perform operations on intermediate results within the chain.
(1..10) .tap {|x| puts "original: #{x}" } .to_a .tap {|x| puts "array: #{x}" } .select {|x| x.even? } .tap {|x| puts "evens: #{x}" } .map {|x| x*x } .tap {|x| puts "squares: #{x}" }
Returns arg converted to a float. Numeric
types are converted directly, and with exception to String
and nil
the rest are converted using arg.to_f
. Converting a String
with invalid characters will result in a ArgumentError
. Converting nil
generates a TypeError
. Exceptions can be suppressed by passing exception: false
.
Float(1) #=> 1.0 Float("123.456") #=> 123.456 Float("123.0_badstring") #=> ArgumentError: invalid value for Float(): "123.0_badstring" Float(nil) #=> TypeError: can't convert nil into Float Float("123.0_badstring", exception: false) #=> nil
Returns the string resulting from formatting objects
into format_string
.
For details on format_string
, see Format Specifications.
Equivalent to Proc.new
, except the resulting Proc
objects check the number of parameters passed when called.
Returns x/y
or arg
as a Rational
.
Rational(2, 3) #=> (2/3) Rational(5) #=> (5/1) Rational(0.5) #=> (1/2) Rational(0.3) #=> (5404319552844595/18014398509481984) Rational("2/3") #=> (2/3) Rational("0.3") #=> (3/10) Rational("10 cents") #=> ArgumentError Rational(nil) #=> TypeError Rational(1, nil) #=> TypeError Rational("10 cents", exception: false) #=> nil
Syntax of the string form:
string form = extra spaces , rational , extra spaces ; rational = [ sign ] , unsigned rational ; unsigned rational = numerator | numerator , "/" , denominator ; numerator = integer part | fractional part | integer part , fractional part ; denominator = digits ; integer part = digits ; fractional part = "." , digits , [ ( "e" | "E" ) , [ sign ] , digits ] ; sign = "-" | "+" ; digits = digit , { digit | "_" , digit } ; digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" ; extra spaces = ? \s* ? ;
See also String#to_r
.
Deprecated. Use block_given? instead.