Returns true
if any member of enum equals obj. Equality is tested using ==
.
IO.constants.include? :SEEK_SET #=> true IO.constants.include? :SEEK_NO_FURTHER #=> false IO.constants.member? :SEEK_SET #=> true IO.constants.member? :SEEK_NO_FURTHER #=> false
Enumerates over the items, chunking them together based on the return value of the block.
Consecutive elements which return the same block value are chunked together.
For example, consecutive even numbers and odd numbers can be chunked as follows.
[3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5].chunk { |n| n.even? }.each { |even, ary| p [even, ary] } #=> [false, [3, 1]] # [true, [4]] # [false, [1, 5, 9]] # [true, [2, 6]] # [false, [5, 3, 5]]
This method is especially useful for sorted series of elements. The following example counts words for each initial letter.
open("/usr/share/dict/words", "r:iso-8859-1") { |f| f.chunk { |line| line.ord }.each { |ch, lines| p [ch.chr, lines.length] } } #=> ["\n", 1] # ["A", 1327] # ["B", 1372] # ["C", 1507] # ["D", 791] # ...
The following key values have special meaning:
nil
and :_separator
specifies that the elements should be dropped.
:_alone
specifies that the element should be chunked by itself.
Any other symbols that begin with an underscore will raise an error:
items.chunk { |item| :_underscore } #=> RuntimeError: symbols beginning with an underscore are reserved
nil
and :_separator
can be used to ignore some elements.
For example, the sequence of hyphens in svn log can be eliminated as follows:
sep = "-"*72 + "\n" IO.popen("svn log README") { |f| f.chunk { |line| line != sep || nil }.each { |_, lines| pp lines } } #=> ["r20018 | knu | 2008-10-29 13:20:42 +0900 (Wed, 29 Oct 2008) | 2 lines\n", # "\n", # "* README, README.ja: Update the portability section.\n", # "\n"] # ["r16725 | knu | 2008-05-31 23:34:23 +0900 (Sat, 31 May 2008) | 2 lines\n", # "\n", # "* README, README.ja: Add a note about default C flags.\n", # "\n"] # ...
Paragraphs separated by empty lines can be parsed as follows:
File.foreach("README").chunk { |line| /\A\s*\z/ !~ line || nil }.each { |_, lines| pp lines }
:_alone
can be used to force items into their own chunk. For example, you can put lines that contain a URL by themselves, and chunk the rest of the lines together, like this:
pattern = /http/ open(filename) { |f| f.chunk { |line| line =~ pattern ? :_alone : true }.each { |key, lines| pp lines } }
Returns system configuration directory.
This is typically “/etc”, but is modified by the prefix used when Ruby was compiled. For example, if Ruby is built and installed in /usr/local, returns “/usr/local/etc”.
Returns the system information obtained by uname system call.
The return value is a hash which has 5 keys at least:
:sysname, :nodename, :release, :version, :machine
Example:
require 'etc' require 'pp' pp Etc.uname #=> {:sysname=>"Linux", # :nodename=>"boron", # :release=>"2.6.18-6-xen-686", # :version=>"#1 SMP Thu Nov 5 19:54:42 UTC 2009", # :machine=>"i686"}
Returns system configuration variable using sysconf().
name should be a constant under Etc
which begins with SC_
.
The return value is an integer or nil. nil means indefinite limit. (sysconf() returns -1 but errno is not set.)
Etc.sysconf(Etc::SC_ARG_MAX) #=> 2097152 Etc.sysconf(Etc::SC_LOGIN_NAME_MAX) #=> 256
Returns system configuration variable using confstr().
name should be a constant under Etc
which begins with CS_
.
The return value is a string or nil. nil means no configuration-defined value. (confstr() returns 0 but errno is not set.)
Etc.confstr(Etc::CS_PATH) #=> "/bin:/usr/bin" # GNU/Linux Etc.confstr(Etc::CS_GNU_LIBC_VERSION) #=> "glibc 2.18" Etc.confstr(Etc::CS_GNU_LIBPTHREAD_VERSION) #=> "NPTL 2.18"
Returns the hexadecimal representation of a memory pointer address addr
Example:
lib = Fiddle.dlopen('/lib64/libc-2.15.so') => #<Fiddle::Handle:0x00000001342460> lib['strcpy'].to_s(16) => "7f59de6dd240" Fiddle.dlunwrap(Fiddle.dlwrap(lib['strcpy'].to_s(16))) => "7f59de6dd240"
Encodes string using Ruby’s String.encode
Returns an inspect() string summarizing the object state.
Returns self, for backward compatibility.
Returns true
if the named file is a directory, or a symlink that points at a directory, and false
otherwise.
file_name can be an IO
object.
File.directory?(".")
Returns true
if the named file has the sticky bit set.
Returns true
if the named files are identical.
file_1 and file_2 can be an IO
object.
open("a", "w") {} p File.identical?("a", "a") #=> true p File.identical?("a", "./a") #=> true File.link("a", "b") p File.identical?("a", "b") #=> true File.symlink("a", "c") p File.identical?("a", "c") #=> true open("d", "w") {} p File.identical?("a", "d") #=> false
The number of times GC
occurred.
It returns the number of times GC
occurred since the process started.
Invokes the block with a Benchmark::Report object, which may be used to collect and report on the results of individual benchmark tests. Reserves label_width
leading spaces for labels on each line. Prints caption
at the top of the report, and uses format
to format each line. Returns an array of Benchmark::Tms
objects.
If the block returns an array of Benchmark::Tms
objects, these will be used to format additional lines of output. If labels
parameter are given, these are used to label these extra lines.
Note: Other methods provide a simpler interface to this one, and are suitable for nearly all benchmarking requirements. See the examples in Benchmark
, and the bm
and bmbm
methods.
Example:
require 'benchmark' include Benchmark # we need the CAPTION and FORMAT constants n = 5000000 Benchmark.benchmark(CAPTION, 7, FORMAT, ">total:", ">avg:") do |x| tf = x.report("for:") { for i in 1..n; a = "1"; end } tt = x.report("times:") { n.times do ; a = "1"; end } tu = x.report("upto:") { 1.upto(n) do ; a = "1"; end } [tf+tt+tu, (tf+tt+tu)/3] end
Generates:
user system total real for: 0.970000 0.000000 0.970000 ( 0.970493) times: 0.990000 0.000000 0.990000 ( 0.989542) upto: 0.970000 0.000000 0.970000 ( 0.972854) >total: 2.930000 0.000000 2.930000 ( 2.932889) >avg: 0.976667 0.000000 0.976667 ( 0.977630)
Returns the elapsed real time used to execute the given block.
Invokes the block with a Benchmark::Report object, which may be used to collect and report on the results of individual benchmark tests. Reserves label_width
leading spaces for labels on each line. Prints caption
at the top of the report, and uses format
to format each line. Returns an array of Benchmark::Tms
objects.
If the block returns an array of Benchmark::Tms
objects, these will be used to format additional lines of output. If labels
parameter are given, these are used to label these extra lines.
Note: Other methods provide a simpler interface to this one, and are suitable for nearly all benchmarking requirements. See the examples in Benchmark
, and the bm
and bmbm
methods.
Example:
require 'benchmark' include Benchmark # we need the CAPTION and FORMAT constants n = 5000000 Benchmark.benchmark(CAPTION, 7, FORMAT, ">total:", ">avg:") do |x| tf = x.report("for:") { for i in 1..n; a = "1"; end } tt = x.report("times:") { n.times do ; a = "1"; end } tu = x.report("upto:") { 1.upto(n) do ; a = "1"; end } [tf+tt+tu, (tf+tt+tu)/3] end
Generates:
user system total real for: 0.970000 0.000000 0.970000 ( 0.970493) times: 0.990000 0.000000 0.990000 ( 0.989542) upto: 0.970000 0.000000 0.970000 ( 0.972854) >total: 2.930000 0.000000 2.930000 ( 2.932889) >avg: 0.976667 0.000000 0.976667 ( 0.977630)
Returns the elapsed real time used to execute the given block.
Get the configuration of the current server.
If there is no current server, this returns the default configuration. See current_server
and DRbServer::make_config.
Get the configuration of the current server.
If there is no current server, this returns the default configuration. See current_server
and DRbServer::make_config.
Get the front object of the current server.
This raises a DRbServerNotFound
error if there is no current server. See current_server
.
Get the front object of the current server.
This raises a DRbServerNotFound
error if there is no current server. See current_server
.