Returns true if path
matches against pattern
. The pattern is not a regular expression; instead it follows rules similar to shell filename globbing. It may contain the following metacharacters:
*
Matches any file. Can be restricted by other values in the glob. Equivalent to / .* /x
in regexp.
*
Matches all files regular files
c*
Matches all files beginning with c
*c
Matches all files ending with c
*c*
Matches all files that have c
in them (including at the beginning or end).
To match hidden files (that start with a .
set the File::FNM_DOTMATCH flag.
**
Matches directories recursively or files expansively.
?
Matches any one character. Equivalent to /.{1}/
in regexp.
[set]
Matches any one character in set
. Behaves exactly like character sets in Regexp
, including set negation ([^a-z]
).
\
Escapes the next metacharacter.
{a,b}
Matches pattern a and pattern b if File::FNM_EXTGLOB flag is enabled. Behaves like a Regexp
union ((?:a|b)
).
flags
is a bitwise OR of the FNM_XXX
constants. The same glob pattern and flags are used by Dir::glob
.
Examples:
File.fnmatch('cat', 'cat') #=> true # match entire string File.fnmatch('cat', 'category') #=> false # only match partial string File.fnmatch('c{at,ub}s', 'cats') #=> false # { } isn't supported by default File.fnmatch('c{at,ub}s', 'cats', File::FNM_EXTGLOB) #=> true # { } is supported on FNM_EXTGLOB File.fnmatch('c?t', 'cat') #=> true # '?' match only 1 character File.fnmatch('c??t', 'cat') #=> false # ditto File.fnmatch('c*', 'cats') #=> true # '*' match 0 or more characters File.fnmatch('c*t', 'c/a/b/t') #=> true # ditto File.fnmatch('ca[a-z]', 'cat') #=> true # inclusive bracket expression File.fnmatch('ca[^t]', 'cat') #=> false # exclusive bracket expression ('^' or '!') File.fnmatch('cat', 'CAT') #=> false # case sensitive File.fnmatch('cat', 'CAT', File::FNM_CASEFOLD) #=> true # case insensitive File.fnmatch('cat', 'CAT', File::FNM_SYSCASE) #=> true or false # depends on the system default File.fnmatch('?', '/', File::FNM_PATHNAME) #=> false # wildcard doesn't match '/' on FNM_PATHNAME File.fnmatch('*', '/', File::FNM_PATHNAME) #=> false # ditto File.fnmatch('[/]', '/', File::FNM_PATHNAME) #=> false # ditto File.fnmatch('\?', '?') #=> true # escaped wildcard becomes ordinary File.fnmatch('\a', 'a') #=> true # escaped ordinary remains ordinary File.fnmatch('\a', '\a', File::FNM_NOESCAPE) #=> true # FNM_NOESCAPE makes '\' ordinary File.fnmatch('[\?]', '?') #=> true # can escape inside bracket expression File.fnmatch('*', '.profile') #=> false # wildcard doesn't match leading File.fnmatch('*', '.profile', File::FNM_DOTMATCH) #=> true # period by default. File.fnmatch('.*', '.profile') #=> true rbfiles = '**' '/' '*.rb' # you don't have to do like this. just write in single string. File.fnmatch(rbfiles, 'main.rb') #=> false File.fnmatch(rbfiles, './main.rb') #=> false File.fnmatch(rbfiles, 'lib/song.rb') #=> true File.fnmatch('**.rb', 'main.rb') #=> true File.fnmatch('**.rb', './main.rb') #=> false File.fnmatch('**.rb', 'lib/song.rb') #=> true File.fnmatch('*', 'dave/.profile') #=> true pattern = '*' '/' '*' File.fnmatch(pattern, 'dave/.profile', File::FNM_PATHNAME) #=> false File.fnmatch(pattern, 'dave/.profile', File::FNM_PATHNAME | File::FNM_DOTMATCH) #=> true pattern = '**' '/' 'foo' File.fnmatch(pattern, 'a/b/c/foo', File::FNM_PATHNAME) #=> true File.fnmatch(pattern, '/a/b/c/foo', File::FNM_PATHNAME) #=> true File.fnmatch(pattern, 'c:/a/b/c/foo', File::FNM_PATHNAME) #=> true File.fnmatch(pattern, 'a/.b/c/foo', File::FNM_PATHNAME) #=> false File.fnmatch(pattern, 'a/.b/c/foo', File::FNM_PATHNAME | File::FNM_DOTMATCH) #=> true
MatchData
encapsulates the result of matching a Regexp
against string. It is returned by Regexp#match
and String#match
, and also stored in a global variable returned by Regexp.last_match
.
Usage:
url = 'https://docs.ruby-lang.org/en/2.5.0/MatchData.html' m = url.match(/(\d\.?)+/) # => #<MatchData "2.5.0" 1:"0"> m.string # => "https://docs.ruby-lang.org/en/2.5.0/MatchData.html" m.regexp # => /(\d\.?)+/ # entire matched substring: m[0] # => "2.5.0" # Working with unnamed captures m = url.match(%r{([^/]+)/([^/]+)\.html$}) m.captures # => ["2.5.0", "MatchData"] m[1] # => "2.5.0" m.values_at(1, 2) # => ["2.5.0", "MatchData"] # Working with named captures m = url.match(%r{(?<version>[^/]+)/(?<module>[^/]+)\.html$}) m.captures # => ["2.5.0", "MatchData"] m.named_captures # => {"version"=>"2.5.0", "module"=>"MatchData"} m[:version] # => "2.5.0" m.values_at(:version, :module) # => ["2.5.0", "MatchData"] # Numerical indexes are working, too m[1] # => "2.5.0" m.values_at(1, 2) # => ["2.5.0", "MatchData"]
Parts of last MatchData
(returned by Regexp.last_match
) are also aliased as global variables:
$~
is Regexp.last_match
;
$&
is Regexp.last_match
[0]
;
$1
, $2
, and so on are Regexp.last_match
[i]
(captures by number);
$`
is Regexp.last_match
.pre_match
;
$'
is Regexp.last_match
.post_match
;
$+
is Regexp.last_match
[-1]
(the last capture).
See also “Special global variables” section in Regexp
documentation.
The Matrix
class represents a mathematical matrix. It provides methods for creating matrices, operating on them arithmetically and algebraically, and determining their mathematical properties such as trace, rank, inverse, determinant, or eigensystem.
Raised when attempting to convert special float values (in particular Infinity
or NaN
) to numerical classes which don’t support them.
Float::INFINITY.to_r #=> FloatDomainError: Infinity
Provides mathematical functions.
Example:
require "bigdecimal/math" include BigMath a = BigDecimal((PI(100)/2).to_s) puts sin(a,100) # => 0.99999999999999999999......e0
The Benchmark
module provides methods to measure and report the time used to execute Ruby code.
Measure the time to construct the string given by the expression "a"*1_000_000_000
:
require 'benchmark' puts Benchmark.measure { "a"*1_000_000_000 }
On my machine (OSX 10.8.3 on i5 1.7 GHz) this generates:
0.350000 0.400000 0.750000 ( 0.835234)
This report shows the user CPU time, system CPU time, the sum of the user and system CPU times, and the elapsed real time. The unit of time is seconds.
Do some experiments sequentially using the bm
method:
require 'benchmark' n = 5000000 Benchmark.bm do |x| x.report { for i in 1..n; a = "1"; end } x.report { n.times do ; a = "1"; end } x.report { 1.upto(n) do ; a = "1"; end } end
The result:
user system total real 1.010000 0.000000 1.010000 ( 1.014479) 1.000000 0.000000 1.000000 ( 0.998261) 0.980000 0.000000 0.980000 ( 0.981335)
Continuing the previous example, put a label in each report:
require 'benchmark' n = 5000000 Benchmark.bm(7) do |x| x.report("for:") { for i in 1..n; a = "1"; end } x.report("times:") { n.times do ; a = "1"; end } x.report("upto:") { 1.upto(n) do ; a = "1"; end } end
The result:
user system total real for: 1.010000 0.000000 1.010000 ( 1.015688) times: 1.000000 0.000000 1.000000 ( 1.003611) upto: 1.030000 0.000000 1.030000 ( 1.028098)
The times for some benchmarks depend on the order in which items are run. These differences are due to the cost of memory allocation and garbage collection. To avoid these discrepancies, the bmbm
method is provided. For example, to compare ways to sort an array of floats:
require 'benchmark' array = (1..1000000).map { rand } Benchmark.bmbm do |x| x.report("sort!") { array.dup.sort! } x.report("sort") { array.dup.sort } end
The result:
Rehearsal ----------------------------------------- sort! 1.490000 0.010000 1.500000 ( 1.490520) sort 1.460000 0.000000 1.460000 ( 1.463025) -------------------------------- total: 2.960000sec user system total real sort! 1.460000 0.000000 1.460000 ( 1.460465) sort 1.450000 0.010000 1.460000 ( 1.448327)
Report statistics of sequential experiments with unique labels, using the benchmark
method:
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
The result:
user system total real for: 0.950000 0.000000 0.950000 ( 0.952039) times: 0.980000 0.000000 0.980000 ( 0.984938) upto: 0.950000 0.000000 0.950000 ( 0.946787) >total: 2.880000 0.000000 2.880000 ( 2.883764) >avg: 0.960000 0.000000 0.960000 ( 0.961255)
mkmf.rb is used by Ruby C extensions to generate a Makefile which will correctly compile and link the C extension to Ruby and a third-party library.
The Math
module contains module functions for basic trigonometric and transcendental functions. See class Float
for a list of constants that define Ruby’s floating point accuracy.
Domains and codomains are given only for real (not complex) numbers.
Generated when trying to lookup a gem to indicate that the gem was found, but that it isn’t usable on the current platform.
fetch and install read these and report them to the user to aid in figuring out why a gem couldn’t be installed.
Raised when a gem dependencies file specifies a ruby version that does not match the current version.
Map from option/keyword string to object with completion.
Individual switch class. Not important to the user.
Defined within Switch
are several Switch-derived classes: NoArgument
, RequiredArgument
, etc.
The command manager registers and installs all the individual sub-commands supported by the gem command.
Extra commands can be provided by writing a rubygems_plugin.rb file in an installed gem. You should register your command against the Gem::CommandManager
instance, like this:
# file rubygems_plugin.rb require 'rubygems/command_manager' Gem::CommandManager.instance.register_command :edit
You should put the implementation of your command in rubygems/commands.
# file rubygems/commands/edit_command.rb class Gem::Commands::EditCommand < Gem::Command # ... end
See Gem::Command
for instructions on writing gem commands.
An error that indicates we weren’t able to fetch some data from a source