Returns self
.
Convert self
to locale encoding
Splits str
into an array of tokens in the same way the UNIX Bourne shell does.
See Shellwords.shellsplit
for details.
Escapes str
so that it can be safely used in a Bourne shell command line.
See Shellwords.shellescape
for details.
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
.
Terminates the fiber by raising an uncatchable exception. It only terminates the given fiber and no other fiber, returning nil
to another fiber if that fiber was calling resume
or transfer
.
Fiber#kill
only interrupts another fiber when it is in Fiber.yield
. If called on the current fiber then it raises that exception at the Fiber#kill
call site.
If the fiber has not been started, transition directly to the terminated state.
If the fiber is already terminated, does nothing.
Raises FiberError
if called on a fiber belonging to another thread.
Returns true if the fiber can still be resumed (or transferred to). After finishing execution of the fiber block this method will always return false
.
Returns the current position of self
; see Dir As Stream-Like:
dir = Dir.new('example') dir.tell # => 0 dir.read # => "." dir.tell # => 1
Returns a File::Stat
object for the file at filepath
(see File::Stat
):
File.stat('t.txt').class # => File::Stat
Like File::stat
, but does not follow the last symbolic link; instead, returns a File::Stat
object for the link itself.
File.symlink('t.txt', 'symlink') File.stat('symlink').size # => 47 File.lstat('symlink').size # => 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.
Like File#stat
, but does not follow the last symbolic link; instead, returns a File::Stat
object for the link itself:
File.symlink('t.txt', 'symlink') f = File.new('symlink') f.stat.size # => 47 f.lstat.size # => 11
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.
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
Returns the hash of available encoding alias and original encoding name.
Encoding.aliases #=> {"BINARY"=>"ASCII-8BIT", "ASCII"=>"US-ASCII", "ANSI_X3.4-1968"=>"US-ASCII", "SJIS"=>"Windows-31J", "eucJP"=>"EUC-JP", "CP932"=>"Windows-31J"}
Return the status value associated with this system exit.
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
.
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?
.
Returns the number of decimal digits following the decimal digits in self
.
BigDecimal("0").scale # => 0 BigDecimal("1").scale # => 0 BigDecimal("1.1").scale # => 1 BigDecimal("3.1415").scale # => 4 BigDecimal("-1e20").precision # => 0 BigDecimal("1e-20").precision # => 20 BigDecimal("Infinity").scale # => 0 BigDecimal("-Infinity").scale # => 0 BigDecimal("NaN").scale # => 0
Returns a simpler approximation of the value if the optional argument eps
is given (rat-|eps| <= result <= rat+|eps|), self otherwise.
r = Rational(5033165, 16777216) r.rationalize #=> (5033165/16777216) r.rationalize(Rational('0.01')) #=> (3/10) r.rationalize(Rational('0.1')) #=> (1/3)
Returns a new Date object formed fom the arguments.
With no arguments, returns the date for January 1, -4712:
Date.ordinal.to_s # => "-4712-01-01"
With argument year
, returns the date for January 1 of that year:
Date.ordinal(2001).to_s # => "2001-01-01" Date.ordinal(-2001).to_s # => "-2001-01-01"
With positive argument yday
== n
, returns the date for the nth
day of the given year:
Date.ordinal(2001, 14).to_s # => "2001-01-14"
With negative argument yday
, counts backward from the end of the year:
Date.ordinal(2001, -14).to_s # => "2001-12-18"
Raises an exception if yday
is zero or out of range.
See argument start.
Returns a new Date object constructed from the arguments.
Argument cwyear
gives the year, and should be an integer.
Argument cweek
gives the index of the week within the year, and should be in range (1..53) or (-53..-1); in some years, 53 or -53 will be out-of-range; if negative, counts backward from the end of the year:
Date.commercial(2022, 1, 1).to_s # => "2022-01-03" Date.commercial(2022, 52, 1).to_s # => "2022-12-26"
Argument cwday
gives the indes of the weekday within the week, and should be in range (1..7) or (-7..-1); 1 or -7 is Monday; if negative, counts backward from the end of the week:
Date.commercial(2022, 1, 1).to_s # => "2022-01-03" Date.commercial(2022, 1, -7).to_s # => "2022-01-03"
When cweek
is 1:
If January 1 is a Friday, Saturday, or Sunday, the first week begins in the week after:
Date::ABBR_DAYNAMES[Date.new(2023, 1, 1).wday] # => "Sun" Date.commercial(2023, 1, 1).to_s # => "2023-01-02" Date.commercial(2023, 1, 7).to_s # => "2023-01-08"
Otherwise, the first week is the week of January 1, which may mean some of the days fall on the year before:
Date::ABBR_DAYNAMES[Date.new(2020, 1, 1).wday] # => "Wed" Date.commercial(2020, 1, 1).to_s # => "2019-12-30" Date.commercial(2020, 1, 7).to_s # => "2020-01-05"
See argument start.
Related: Date.jd
, Date.new
, Date.ordinal
.
Returns the Julian start date for calendar reform; if not an infinity, the returned value is suitable for passing to Date#jd
:
d = Date.new(2001, 2, 3, Date::ITALY) s = d.start # => 2299161.0 Date.jd(s).to_s # => "1582-10-15" d = Date.new(2001, 2, 3, Date::ENGLAND) s = d.start # => 2361222.0 Date.jd(s).to_s # => "1752-09-14" Date.new(2001, 2, 3, Date::GREGORIAN).start # => -Infinity Date.new(2001, 2, 3, Date::JULIAN).start # => Infinity
See argument start.