Returns the numerator. The result is machine dependent.
n = 0.3.numerator #=> 5404319552844595 d = 0.3.denominator #=> 18014398509481984 n.fdiv(d) #=> 0.3
See also Float#denominator
.
Returns the denominator (always positive). The result is machine dependent.
See also Float#numerator
.
Returns a simpler approximation of the value (flt-|eps| <= result <= flt+|eps|). If the optional argument eps
is not given, it will be chosen automatically.
0.3.rationalize #=> (3/10) 1.333.rationalize #=> (1333/1000) 1.333.rationalize(0.01) #=> (4/3)
See also Float#to_r
.
Returns the dirpath
string that was used to create self
(or nil
if created by method Dir.for_fd
):
Dir.new('example').path # => "example"
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 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 File.fnmatch('**/*.rb', 'main.rb') #=> false File.fnmatch('**/*.rb', './main.rb') #=> false File.fnmatch('**/*.rb', '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 File.fnmatch('**/foo', 'a/b/c/foo', File::FNM_PATHNAME) #=> true File.fnmatch('**/foo', '/a/b/c/foo', File::FNM_PATHNAME) #=> true File.fnmatch('**/foo', 'c:/a/b/c/foo', File::FNM_PATHNAME) #=> true File.fnmatch('**/foo', 'a/.b/c/foo', File::FNM_PATHNAME) #=> false File.fnmatch('**/foo', 'a/.b/c/foo', File::FNM_PATHNAME | File::FNM_DOTMATCH) #=> true
Returns the last access time for the named file as a Time
object.
file_name can be an IO
object.
File.atime("testfile") #=> Wed Apr 09 08:51:48 CDT 2003
Truncates the file file_name to be at most integer bytes long. Not available on all platforms.
f = File.new("out", "w") f.write("1234567890") #=> 10 f.close #=> nil File.truncate("out", 5) #=> 0 File.size("out") #=> 5
Returns the real (absolute) pathname of pathname in the actual filesystem not containing symlinks or useless dots.
If dir_string is given, it is used as a base directory for interpreting relative pathname instead of the current directory.
All components of the pathname must exist when this method is called.
Returns the real (absolute) pathname of pathname in the actual filesystem. The real pathname doesn’t contain symlinks or useless dots.
If dir_string is given, it is used as a base directory for interpreting relative pathname instead of the current directory.
The last component of the real pathname can be nonexistent.
Returns the string representation of the path
File.path(File::NULL) #=> "/dev/null" File.path(Pathname.new("/tmp")) #=> "/tmp"
Returns the last access time (a Time
object) for file, or epoch if file has not been accessed.
File.new("testfile").atime #=> Wed Dec 31 18:00:00 CST 1969
Truncates file to at most integer bytes. The file must be opened for writing. Not available on all platforms.
f = File.new("out", "w") f.syswrite("1234567890") #=> 10 f.truncate(5) #=> 0 f.close() #=> nil File.size("out") #=> 5
Returns true
if the named file is readable by the effective user and group id of this process. See eaccess(3).
Note that some OS-level security features may cause this to return true even though the file is not readable by the effective user/group.
Returns true
if the named file is writable by the effective user and group id of this process. See eaccess(3).
Note that some OS-level security features may cause this to return true even though the file is not writable by the effective user/group.
Returns true
if the named file is executable by the effective user and group id of this process. See eaccess(3).
Windows does not support execute permissions separately from read permissions. On Windows, a file is only considered executable if it ends in .bat, .cmd, .com, or .exe.
Note that some OS-level security features may cause this to return true even though the file is not executable by the effective user/group.
Checks the compatibility of two objects.
If the objects are both strings they are compatible when they are concatenatable. The encoding of the concatenated string will be returned if they are compatible, nil if they are not.
Encoding.compatible?("\xa1".force_encoding("iso-8859-1"), "b") #=> #<Encoding:ISO-8859-1> Encoding.compatible?( "\xa1".force_encoding("iso-8859-1"), "\xa1\xa1".force_encoding("euc-jp")) #=> nil
If the objects are non-strings their encodings are compatible when they have an encoding and:
Either encoding is US-ASCII compatible
One of the encodings is a 7-bit encoding
The primary interface to this library. Use to setup delegation when defining your class.
class MyClass < DelegateClass(ClassToDelegateTo) # Step 1 def initialize super(obj_of_ClassToDelegateTo) # Step 2 end end
or:
MyClass = DelegateClass(ClassToDelegateTo) do # Step 1 def initialize super(obj_of_ClassToDelegateTo) # Step 2 end end
Here’s a sample of use from Tempfile
which is really a File
object with a few special rules about storage location and when the File
should be deleted. That makes for an almost textbook perfect example of how to use delegation.
class Tempfile < DelegateClass(File) # constant and class member data initialization... def initialize(basename, tmpdir=Dir::tmpdir) # build up file path/name in var tmpname... @tmpfile = File.open(tmpname, File::RDWR|File::CREAT|File::EXCL, 0600) # ... super(@tmpfile) # below this point, all methods of File are supported... end # ... end
Return the matchee associated with this NoMatchingPatternKeyError
exception.
In the first form, returns an array of the names of all constants accessible from the point of call. This list includes the names of all modules and classes defined in the global scope.
Module.constants.first(4) # => [:ARGF, :ARGV, :ArgumentError, :Array] Module.constants.include?(:SEEK_SET) # => false class IO Module.constants.include?(:SEEK_SET) # => true end
The second form calls the instance method constants
.
The first form is equivalent to attr_reader
. The second form is equivalent to attr_accessor(name)
but deprecated. The last form is equivalent to attr_reader(name)
but deprecated. Returns an array of defined method names as symbols.
Returns an array of the names of the constants accessible in mod. This includes the names of constants in any included modules (example at start of section), unless the inherit parameter is set to false
.
The implementation makes no guarantees about the order in which the constants are yielded.
IO.constants.include?(:SYNC) #=> true IO.constants(false).include?(:SYNC) #=> false
Also see Module#const_defined?
.
With no arguments, sets the default visibility for subsequently defined methods to private. With arguments, sets the named methods to have private visibility. String
arguments are converted to symbols. An Array
of Symbols and/or Strings is also accepted. If a single argument is passed, it is returned. If no argument is passed, nil is returned. If multiple arguments are passed, the arguments are returned as an array.
module Mod def a() end def b() end private def c() end private :a end Mod.private_instance_methods #=> [:a, :c]
Note that to show a private method on RDoc
, use :doc:
.
Returns a new Date object constructed from the present date:
Date.today.to_s # => "2022-07-06"
See argument start.