Results for: "String# "

Returns a string representation of self, formatted according to the given string format. See Formats for Dates and Times.

Behaves like IO.write, except that the stream is opened in binary mode with ASCII-8BIT encoding.

When called from class IO (but not subclasses of IO), this method has potential security vulnerabilities if called with untrusted input; see Command Injection.

Writes the given objects to the stream; returns nil. Appends the output record separator $OUTPUT_RECORD_SEPARATOR ($\), if it is not nil. See Line IO.

With argument objects given, for each object:

• Converts via its method to_s if not a string.

• Writes to the stream.

• If not the last object, writes the output field separator $OUTPUT_FIELD_SEPARATOR ($,) if it is not nil.

With default separators:

f = File.open('t.tmp', 'w+')
objects = [0, 0.0, Rational(0, 1), Complex(0, 0), :zero, 'zero']
p $OUTPUT_RECORD_SEPARATOR
p $OUTPUT_FIELD_SEPARATOR
f.print(*objects)
f.rewind
p f.read
f.close

Output:

nil
nil
"00.00/10+0izerozero"

With specified separators:

$\ = "\n"
$, = ','
f.rewind
f.print(*objects)
f.rewind
p f.read

Output:

"0,0.0,0/1,0+0i,zero,zero\n"

With no argument given, writes the content of $_ (which is usually the most recent user input):

f = File.open('t.tmp', 'w+')
gets # Sets $_ to the most recent user input.
f.print
f.close

Formats and writes objects to the stream.

For details on format_string, see Format Specifications.

Returns an array containing the elements in self, if a finite collection; raises an exception otherwise.

(1..4).to_a     # => [1, 2, 3, 4]
(1...4).to_a    # => [1, 2, 3]
('a'..'d').to_a # => ["a", "b", "c", "d"]

Range#entries is an alias for Range#to_a.

Returns the Encoding object that represents the encoding of obj.

Returns the values in self as an array:

Customer = Struct.new(:name, :address, :zip)
joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345)
joe.to_a # => ["Joe Smith", "123 Maple, Anytown NC", 12345]

Struct#values and Struct#deconstruct are aliases for Struct#to_a.

Related: members.

Equivalent to self.to_s.encoding; see String#encoding.

Callback invoked whenever a subclass of the current class is created.

Example:

class Foo
  def self.inherited(subclass)
    puts "New subclass: #{subclass}"
  end
end

class Bar < Foo
end

class Baz < Bar
end

produces:

New subclass: Bar
New subclass: Baz

Writes contents to the file, opening it in binary mode.

See File.binwrite.

Return the entries (files and subdirectories) in the directory, each as a Pathname object.

The results contains just the names in the directory, without any trailing slashes or recursive look-up.

pp Pathname.new('/usr/local').entries
#=> [#<Pathname:share>,
#    #<Pathname:lib>,
#    #<Pathname:..>,
#    #<Pathname:include>,
#    #<Pathname:etc>,
#    #<Pathname:bin>,
#    #<Pathname:man>,
#    #<Pathname:games>,
#    #<Pathname:.>,
#    #<Pathname:sbin>,
#    #<Pathname:src>]

The result may contain the current directory #<Pathname:.> and the parent directory #<Pathname:..>.

If you don’t want . and .. and want directories, consider Pathname#children.

This method is called when strong warning is produced by the parser. fmt and args is printf style.

Return encoding of the source.

Obtains address information for nodename:servname.

Note that Addrinfo.getaddrinfo provides the same functionality in an object oriented style.

family should be an address family such as: :INET, :INET6, etc.

socktype should be a socket type such as: :STREAM, :DGRAM, :RAW, etc.

protocol should be a protocol defined in the family, and defaults to 0 for the family.

flags should be bitwise OR of Socket::AI_* constants.

Socket.getaddrinfo("www.ruby-lang.org", "http", nil, :STREAM)
#=> [["AF_INET", 80, "carbon.ruby-lang.org", "221.186.184.68", 2, 1, 6]] # PF_INET/SOCK_STREAM/IPPROTO_TCP

Socket.getaddrinfo("localhost", nil)
#=> [["AF_INET", 0, "localhost", "127.0.0.1", 2, 1, 6],  # PF_INET/SOCK_STREAM/IPPROTO_TCP
#    ["AF_INET", 0, "localhost", "127.0.0.1", 2, 2, 17], # PF_INET/SOCK_DGRAM/IPPROTO_UDP
#    ["AF_INET", 0, "localhost", "127.0.0.1", 2, 3, 0]]  # PF_INET/SOCK_RAW/IPPROTO_IP

reverse_lookup directs the form of the third element, and has to be one of below. If reverse_lookup is omitted, the default value is nil.

+true+, +:hostname+:  hostname is obtained from numeric address using reverse lookup, which may take a time.
+false+, +:numeric+:  hostname is the same as numeric address.
+nil+:              obey to the current +do_not_reverse_lookup+ flag.

If Addrinfo object is preferred, use Addrinfo.getaddrinfo.

returns a list of addrinfo objects as an array.

This method converts nodename (hostname) and service (port) to addrinfo. Since the conversion is not unique, the result is a list of addrinfo objects.

nodename or service can be nil if no conversion intended.

family, socktype and protocol are hint for preferred protocol. If the result will be used for a socket with SOCK_STREAM, SOCK_STREAM should be specified as socktype. If so, Addrinfo.getaddrinfo returns addrinfo list appropriate for SOCK_STREAM. If they are omitted or nil is given, the result is not restricted.

Similarly, PF_INET6 as family restricts for IPv6.

flags should be bitwise OR of Socket::AI_??? constants such as follows. Note that the exact list of the constants depends on OS.

AI_PASSIVE      Get address to use with bind()
AI_CANONNAME    Fill in the canonical name
AI_NUMERICHOST  Prevent host name resolution
AI_NUMERICSERV  Prevent service name resolution
AI_V4MAPPED     Accept IPv4-mapped IPv6 addresses
AI_ALL          Allow all addresses
AI_ADDRCONFIG   Accept only if any address is assigned

Note that socktype should be specified whenever application knows the usage of the address. Some platform causes an error when socktype is omitted and servname is specified as an integer because some port numbers, 512 for example, are ambiguous without socktype.

Addrinfo.getaddrinfo("www.kame.net", 80, nil, :STREAM)
#=> [#<Addrinfo: 203.178.141.194:80 TCP (www.kame.net)>,
#    #<Addrinfo: [2001:200:dff:fff1:216:3eff:feb1:44d7]:80 TCP (www.kame.net)>]

Writes the given objects to the stream; returns nil. Appends the output record separator $OUTPUT_RECORD_SEPARATOR ($\), if it is not nil. See Line IO.

With argument objects given, for each object:

• Converts via its method to_s if not a string.

• Writes to the stream.

• If not the last object, writes the output field separator $OUTPUT_FIELD_SEPARATOR ($,) if it is not nil.

With default separators:

f = File.open('t.tmp', 'w+')
objects = [0, 0.0, Rational(0, 1), Complex(0, 0), :zero, 'zero']
p $OUTPUT_RECORD_SEPARATOR
p $OUTPUT_FIELD_SEPARATOR
f.print(*objects)
f.rewind
p f.read
f.close

Output:

nil
nil
"00.00/10+0izerozero"

With specified separators:

$\ = "\n"
$, = ','
f.rewind
f.print(*objects)
f.rewind
p f.read

Output:

"0,0.0,0/1,0+0i,zero,zero\n"

With no argument given, writes the content of $_ (which is usually the most recent user input):

f = File.open('t.tmp', 'w+')
gets # Sets $_ to the most recent user input.
f.print
f.close

Formats and writes objects to the stream.

For details on format_string, see Format Specifications.

Creates or retrieves cached CSV objects. For arguments and options, see CSV.new.

This API is not Ractor-safe.

With no block given, returns a CSV object.

The first call to instance creates and caches a CSV object:

s0 = 's0'
csv0 = CSV.instance(s0)
csv0.class # => CSV

Subsequent calls to instance with that same string or io retrieve that same cached object:

csv1 = CSV.instance(s0)
csv1.class # => CSV
csv1.equal?(csv0) # => true # Same CSV object

A subsequent call to instance with a different string or io creates and caches a different CSV object.

s1 = 's1'
csv2 = CSV.instance(s1)
csv2.equal?(csv0) # => false # Different CSV object

All the cached objects remains available:

csv3 = CSV.instance(s0)
csv3.equal?(csv0) # true # Same CSV object
csv4 = CSV.instance(s1)
csv4.equal?(csv2) # true # Same CSV object

When a block is given, calls the block with the created or retrieved CSV object; returns the block’s return value:

CSV.instance(s0) {|csv| :foo } # => :foo

Returns the values in self as an array, to use in pattern matching:

Measure = Data.define(:amount, :unit)

distance = Measure[10, 'km']
distance.deconstruct #=> [10, "km"]

# usage
case distance
in n, 'km' # calls #deconstruct underneath
  puts "It is #{n} 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(n, 'km')
  puts "It is #{n} kilometers away"
# ...
end

Returns the array of captures, which are all matches except m[0]:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m[0]       # => "HX1138"
m.captures # => ["H", "X", "113", "8"]

Related: MatchData.to_a.

Returns the priority of thr. Default is inherited from the current thread which creating the new thread, or zero for the initial main thread; higher-priority thread will run more frequently than lower-priority threads (but lower-priority threads can also run).

This is just hint for Ruby thread scheduler. It may be ignored on some platform.

Thread.current.priority   #=> 0

Sets the priority of thr to integer. Higher-priority threads will run more frequently than lower-priority threads (but lower-priority threads can also run).

This is just hint for Ruby thread scheduler. It may be ignored on some platform.

count1 = count2 = 0
a = Thread.new do
      loop { count1 += 1 }
    end
a.priority = -1

b = Thread.new do
      loop { count2 += 1 }
    end
b.priority = -2
sleep 1   #=> 1
count1    #=> 622504
count2    #=> 5832

Equivalent to:

io.write(sprintf(format_string, *objects))

For details on format_string, see Format Specifications.

With the single argument format_string, formats objects into the string, then writes the formatted string to $stdout:

printf('%4.4d %10s %2.2f', 24, 24, 24.0)

Output (on $stdout):

0024         24 24.00#

With arguments io and format_string, formats objects into the string, then writes the formatted string to io:

printf($stderr, '%4.4d %10s %2.2f', 24, 24, 24.0)

Output (on $stderr):

0024         24 24.00# => nil

With no arguments, does nothing.

Equivalent to $stdout.print(*objects), this method is the straightforward way to write to $stdout.

Writes the given objects to $stdout; returns nil. Appends the output record separator $OUTPUT_RECORD_SEPARATOR $\), if it is not nil.

With argument objects given, for each object:

• Converts via its method to_s if not a string.

• Writes to stdout.

• If not the last object, writes the output field separator $OUTPUT_FIELD_SEPARATOR ($, if it is not nil.

With default separators:

objects = [0, 0.0, Rational(0, 1), Complex(0, 0), :zero, 'zero']
$OUTPUT_RECORD_SEPARATOR
$OUTPUT_FIELD_SEPARATOR
print(*objects)

Output:

nil
nil
00.00/10+0izerozero

With specified separators:

$OUTPUT_RECORD_SEPARATOR = "\n"
$OUTPUT_FIELD_SEPARATOR = ','
print(*objects)

Output:

0,0.0,0/1,0+0i,zero,zero

With no argument given, writes the content of $_ (which is usually the most recent user input):

gets  # Sets $_ to the most recent user input.
print # Prints $_.

Returns the string resulting from formatting objects into format_string.

For details on format_string, see Format Specifications.

Kernel#format is an alias for Kernel#sprintf.