Update the access and modification times of the file.
Same as Pathname#utime
, but does not follow symbolic links.
See File.lutime
.
Parses the given Ruby program read from src
. src
must be a String
or an IO
or a object with a gets
method.
Returns an array of interface addresses. An element of the array is an instance of Socket::Ifaddr
.
This method can be used to find multicast-enabled interfaces:
pp Socket.getifaddrs.reject {|ifaddr| !ifaddr.addr.ip? || (ifaddr.flags & Socket::IFF_MULTICAST == 0) }.map {|ifaddr| [ifaddr.name, ifaddr.ifindex, ifaddr.addr] } #=> [["eth0", 2, #<Addrinfo: 221.186.184.67>], # ["eth0", 2, #<Addrinfo: fe80::216:3eff:fe95:88bb%eth0>]]
Example result on GNU/Linux:
pp Socket.getifaddrs #=> [#<Socket::Ifaddr lo UP,LOOPBACK,RUNNING,0x10000 PACKET[protocol=0 lo hatype=772 HOST hwaddr=00:00:00:00:00:00]>, # #<Socket::Ifaddr eth0 UP,BROADCAST,RUNNING,MULTICAST,0x10000 PACKET[protocol=0 eth0 hatype=1 HOST hwaddr=00:16:3e:95:88:bb] broadcast=PACKET[protocol=0 eth0 hatype=1 HOST hwaddr=ff:ff:ff:ff:ff:ff]>, # #<Socket::Ifaddr sit0 NOARP PACKET[protocol=0 sit0 hatype=776 HOST hwaddr=00:00:00:00]>, # #<Socket::Ifaddr lo UP,LOOPBACK,RUNNING,0x10000 127.0.0.1 netmask=255.0.0.0>, # #<Socket::Ifaddr eth0 UP,BROADCAST,RUNNING,MULTICAST,0x10000 221.186.184.67 netmask=255.255.255.240 broadcast=221.186.184.79>, # #<Socket::Ifaddr lo UP,LOOPBACK,RUNNING,0x10000 ::1 netmask=ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff>, # #<Socket::Ifaddr eth0 UP,BROADCAST,RUNNING,MULTICAST,0x10000 fe80::216:3eff:fe95:88bb%eth0 netmask=ffff:ffff:ffff:ffff::>]
Example result on FreeBSD:
pp Socket.getifaddrs #=> [#<Socket::Ifaddr usbus0 UP,0x10000 LINK[usbus0]>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 LINK[re0 3a:d0:40:9a:fe:e8]>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 10.250.10.18 netmask=255.255.255.? (7 bytes for 16 bytes sockaddr_in) broadcast=10.250.10.255>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 fe80:2::38d0:40ff:fe9a:fee8 netmask=ffff:ffff:ffff:ffff::>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 2001:2e8:408:10::12 netmask=UNSPEC>, # #<Socket::Ifaddr plip0 POINTOPOINT,MULTICAST,0x800 LINK[plip0]>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST LINK[lo0]>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST ::1 netmask=ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST fe80:4::1 netmask=ffff:ffff:ffff:ffff::>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST 127.0.0.1 netmask=255.?.?.? (5 bytes for 16 bytes sockaddr_in)>]
Parses string
or io
using the specified options
.
Argument string
should be a String object; it will be put into a new StringIO
object positioned at the beginning.
Argument io
should be an IO
object that is:
Open for reading; on return, the IO
object will be closed.
Positioned at the beginning. To position at the end, for appending, use method CSV.generate
. For any other positioning, pass a preset StringIO object instead.
Argument options
: see Options for Parsing
headers
Without {option headers
} case.
These examples assume prior execution of:
string = "foo,0\nbar,1\nbaz,2\n" path = 't.csv' File.write(path, string)
With no block given, returns an Array of Arrays formed from the source.
Parse a String:
a_of_a = CSV.parse(string) a_of_a # => [["foo", "0"], ["bar", "1"], ["baz", "2"]]
Parse an open File:
a_of_a = File.open(path) do |file| CSV.parse(file) end a_of_a # => [["foo", "0"], ["bar", "1"], ["baz", "2"]]
With a block given, calls the block with each parsed row:
Parse a String:
CSV.parse(string) {|row| p row }
Output:
["foo", "0"] ["bar", "1"] ["baz", "2"]
Parse an open File:
File.open(path) do |file| CSV.parse(file) {|row| p row } end
Output:
["foo", "0"] ["bar", "1"] ["baz", "2"]
headers
With {option headers
} case.
These examples assume prior execution of:
string = "Name,Count\nfoo,0\nbar,1\nbaz,2\n" path = 't.csv' File.write(path, string)
With no block given, returns a CSV::Table
object formed from the source.
Parse a String:
csv_table = CSV.parse(string, headers: ['Name', 'Count']) csv_table # => #<CSV::Table mode:col_or_row row_count:5>
Parse an open File:
csv_table = File.open(path) do |file| CSV.parse(file, headers: ['Name', 'Count']) end csv_table # => #<CSV::Table mode:col_or_row row_count:4>
With a block given, calls the block with each parsed row, which has been formed into a CSV::Row
object:
Parse a String:
CSV.parse(string, headers: ['Name', 'Count']) {|row| p row }
Output:
# <CSV::Row "Name":"foo" "Count":"0"> # <CSV::Row "Name":"bar" "Count":"1"> # <CSV::Row "Name":"baz" "Count":"2">
Parse an open File:
File.open(path) do |file| CSV.parse(file, headers: ['Name', 'Count']) {|row| p row } end
Output:
# <CSV::Row "Name":"foo" "Count":"0"> # <CSV::Row "Name":"bar" "Count":"1"> # <CSV::Row "Name":"baz" "Count":"2">
Raises an exception if the argument is not a String object or IO object:
# Raises NoMethodError (undefined method `close' for :foo:Symbol) CSV.parse(:foo)
Returns an Array containing field converters; see Field Converters:
csv = CSV.new('') csv.converters # => [] csv.convert(:integer) csv.converters # => [:integer] csv.convert(proc {|x| x.to_s }) csv.converters
Notes that you need to call +Ractor.make_shareable(CSV::Converters
)+ on the main Ractor
to use this method.
With no block, installs a field converter (a Proc).
With a block, defines and installs a custom field converter.
Returns the Array of installed field converters.
Argument converter_name
, if given, should be the name of an existing field converter.
See Field Converters.
With no block, installs a field converter:
csv = CSV.new('') csv.convert(:integer) csv.convert(:float) csv.convert(:date) csv.converters # => [:integer, :float, :date]
The block, if given, is called for each field:
Argument field
is the field value.
Argument field_info
is a CSV::FieldInfo
object containing details about the field.
The examples here assume the prior execution of:
string = "foo,0\nbar,1\nbaz,2\n" path = 't.csv' File.write(path, string)
Example giving a block:
csv = CSV.open(path) csv.convert {|field, field_info| p [field, field_info]; field.upcase } csv.read # => [["FOO", "0"], ["BAR", "1"], ["BAZ", "2"]]
Output:
["foo", #<struct CSV::FieldInfo index=0, line=1, header=nil>] ["0", #<struct CSV::FieldInfo index=1, line=1, header=nil>] ["bar", #<struct CSV::FieldInfo index=0, line=2, header=nil>] ["1", #<struct CSV::FieldInfo index=1, line=2, header=nil>] ["baz", #<struct CSV::FieldInfo index=0, line=3, header=nil>] ["2", #<struct CSV::FieldInfo index=1, line=3, header=nil>]
The block need not return a String object:
csv = CSV.open(path) csv.convert {|field, field_info| field.to_sym } csv.read # => [[:foo, :"0"], [:bar, :"1"], [:baz, :"2"]]
If converter_name
is given, the block is not called:
csv = CSV.open(path) csv.convert(:integer) {|field, field_info| fail 'Cannot happen' } csv.read # => [["foo", 0], ["bar", 1], ["baz", 2]]
Raises a parse-time exception if converter_name
is not the name of a built-in field converter:
csv = CSV.open(path) csv.convert(:nosuch) => [nil] # Raises NoMethodError (undefined method `arity' for nil:NilClass) csv.read
Returns revision information for the erb.rb module.
Returns a new ipaddr built by converting the IPv6 address into a native IPv4 address. If the IP address is not an IPv4-mapped or IPv4-compatible IPv6 address, returns self.
Add separator in summary.
Parses command line arguments argv
in order when environment variable POSIXLY_CORRECT is set, and in permutation mode otherwise. When optional into
keyword argument is provided, the parsed option values are stored there via []=
method (so it can be Hash
, or OpenStruct
, or other similar object).
Same as parse
, but removes switches destructively. Non-option arguments remain in argv
.
Returns the number of mandatory arguments. If the block is declared to take no arguments, returns 0. If the block is known to take exactly n arguments, returns n. If the block has optional arguments, returns -n-1, where n is the number of mandatory arguments, with the exception for blocks that are not lambdas and have only a finite number of optional arguments; in this latter case, returns n. Keyword arguments will be considered as a single additional argument, that argument being mandatory if any keyword argument is mandatory. A proc
with no argument declarations is the same as a block declaring ||
as its arguments.
proc {}.arity #=> 0 proc { || }.arity #=> 0 proc { |a| }.arity #=> 1 proc { |a, b| }.arity #=> 2 proc { |a, b, c| }.arity #=> 3 proc { |*a| }.arity #=> -1 proc { |a, *b| }.arity #=> -2 proc { |a, *b, c| }.arity #=> -3 proc { |x:, y:, z:0| }.arity #=> 1 proc { |*a, x:, y:0| }.arity #=> -2 proc { |a=0| }.arity #=> 0 lambda { |a=0| }.arity #=> -1 proc { |a=0, b| }.arity #=> 1 lambda { |a=0, b| }.arity #=> -2 proc { |a=0, b=0| }.arity #=> 0 lambda { |a=0, b=0| }.arity #=> -1 proc { |a, b=0| }.arity #=> 1 lambda { |a, b=0| }.arity #=> -2 proc { |(a, b), c=0| }.arity #=> 1 lambda { |(a, b), c=0| }.arity #=> -2 proc { |a, x:0, y:0| }.arity #=> 1 lambda { |a, x:0, y:0| }.arity #=> -2
Returns the parameter information of this proc. If the lambda keyword is provided and not nil, treats the proc as a lambda if true and as a non-lambda if false.
prc = proc{|x, y=42, *other|} prc.parameters #=> [[:opt, :x], [:opt, :y], [:rest, :other]] prc = lambda{|x, y=42, *other|} prc.parameters #=> [[:req, :x], [:opt, :y], [:rest, :other]] prc = proc{|x, y=42, *other|} prc.parameters(lambda: true) #=> [[:req, :x], [:opt, :y], [:rest, :other]] prc = lambda{|x, y=42, *other|} prc.parameters(lambda: false) #=> [[:opt, :x], [:opt, :y], [:rest, :other]]
Returns an indication of the number of arguments accepted by a method. Returns a nonnegative integer for methods that take a fixed number of arguments. For Ruby methods that take a variable number of arguments, returns -n-1, where n is the number of required arguments. Keyword arguments will be considered as a single additional argument, that argument being mandatory if any keyword argument is mandatory. For methods written in C, returns -1 if the call takes a variable number of arguments.
class C def one; end def two(a); end def three(*a); end def four(a, b); end def five(a, b, *c); end def six(a, b, *c, &d); end def seven(a, b, x:0); end def eight(x:, y:); end def nine(x:, y:, **z); end def ten(*a, x:, y:); end end c = C.new c.method(:one).arity #=> 0 c.method(:two).arity #=> 1 c.method(:three).arity #=> -1 c.method(:four).arity #=> 2 c.method(:five).arity #=> -3 c.method(:six).arity #=> -3 c.method(:seven).arity #=> -3 c.method(:eight).arity #=> 1 c.method(:nine).arity #=> 1 c.method(:ten).arity #=> -2 "cat".method(:size).arity #=> 0 "cat".method(:replace).arity #=> 1 "cat".method(:squeeze).arity #=> -1 "cat".method(:count).arity #=> -1
Returns the parameter information of this method.
def foo(bar); end method(:foo).parameters #=> [[:req, :bar]] def foo(bar, baz, bat, &blk); end method(:foo).parameters #=> [[:req, :bar], [:req, :baz], [:req, :bat], [:block, :blk]] def foo(bar, *args); end method(:foo).parameters #=> [[:req, :bar], [:rest, :args]] def foo(bar, baz, *args, &blk); end method(:foo).parameters #=> [[:req, :bar], [:req, :baz], [:rest, :args], [:block, :blk]]
Returns an indication of the number of arguments accepted by a method. Returns a nonnegative integer for methods that take a fixed number of arguments. For Ruby methods that take a variable number of arguments, returns -n-1, where n is the number of required arguments. Keyword arguments will be considered as a single additional argument, that argument being mandatory if any keyword argument is mandatory. For methods written in C, returns -1 if the call takes a variable number of arguments.
class C def one; end def two(a); end def three(*a); end def four(a, b); end def five(a, b, *c); end def six(a, b, *c, &d); end def seven(a, b, x:0); end def eight(x:, y:); end def nine(x:, y:, **z); end def ten(*a, x:, y:); end end c = C.new c.method(:one).arity #=> 0 c.method(:two).arity #=> 1 c.method(:three).arity #=> -1 c.method(:four).arity #=> 2 c.method(:five).arity #=> -3 c.method(:six).arity #=> -3 c.method(:seven).arity #=> -3 c.method(:eight).arity #=> 1 c.method(:nine).arity #=> 1 c.method(:ten).arity #=> -2 "cat".method(:size).arity #=> 0 "cat".method(:replace).arity #=> 1 "cat".method(:squeeze).arity #=> -1 "cat".method(:count).arity #=> -1
Returns the parameter information of this method.
def foo(bar); end method(:foo).parameters #=> [[:req, :bar]] def foo(bar, baz, bat, &blk); end method(:foo).parameters #=> [[:req, :bar], [:req, :baz], [:req, :bat], [:block, :blk]] def foo(bar, *args); end method(:foo).parameters #=> [[:req, :bar], [:rest, :args]] def foo(bar, baz, *args, &blk); end method(:foo).parameters #=> [[:req, :bar], [:req, :baz], [:rest, :args], [:block, :blk]]
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.
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
Return the parameters definition of the method or block that the current hook belongs to. Format is the same as for Method#parameters