Returns the modification time for file.
File.new("testfile").mtime #=> Wed Apr 09 08:53:14 CDT 2003
Returns the change time for file (that is, the time directory information about the file was changed, not the file itself).
Note that on Windows (NTFS), returns creation time (birth time).
File.new("testfile").ctime #=> Wed Apr 09 08:53:14 CDT 2003
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 a replicated encoding of enc whose name is name. The new encoding should have the same byte structure of enc. If name is used by another encoding, raise ArgumentError.
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
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
Returns the result of invoking exception.to_s. Normally this returns the exception’s message or name. By supplying a to_str method, exceptions are agreeing to be used where Strings are expected.
Return the status value associated with this system exit.
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.
module Mod def a() end def b() end private def c() end private :a end Mod.private_instance_methods #=> [:a, :c]
Returns True if the value is Not a Number.
Truncate to the nearest integer (by default), returning the result as a BigDecimal.
BigDecimal('3.14159').truncate #=> 3 BigDecimal('8.7').truncate #=> 8 BigDecimal('-9.9').truncate #=> -9
If n is specified and positive, the fractional part of the result has no more than that many digits.
If n is specified and negative, at least that many digits to the left of the decimal point will be 0 in the result.
BigDecimal('3.14159').truncate(3) #=> 3.141 BigDecimal('13345.234').truncate(-2) #=> 13300.0
Returns true if self is a prime number, else returns false.
Iterates the given block int times, passing in values from zero to int - 1.
If no block is given, an Enumerator is returned instead.
5.times do |i| print i, " " end #=> 0 1 2 3 4
As int is already an Integer, all these methods simply return the receiver.
Returns the truncated value (toward zero).
Rational(3).truncate #=> 3 Rational(2, 3).truncate #=> 0 Rational(-3, 2).truncate #=> -1 # decimal - 1 2 3 . 4 5 6 # ^ ^ ^ ^ ^ ^ # precision -3 -2 -1 0 +1 +2 '%f' % Rational('-123.456').truncate(+1) #=> "-123.400000" '%f' % Rational('-123.456').truncate(-1) #=> "-120.000000"
Creates a date object denoting the given ordinal date.
The day of year should be a negative or a positive number (as a relative day from the end of year when negative). It should not be zero.
Date.ordinal(2001) #=> #<Date: 2001-01-01 ...> Date.ordinal(2001,34) #=> #<Date: 2001-02-03 ...> Date.ordinal(2001,-1) #=> #<Date: 2001-12-31 ...>
See also jd and new.
Creates a date object denoting the given week date.
The week and the day of week should be a negative or a positive number (as a relative week/day from the end of year/week when negative). They should not be zero.
Date.commercial(2001) #=> #<Date: 2001-01-01 ...> Date.commercial(2002) #=> #<Date: 2001-12-31 ...> Date.commercial(2001,5,6) #=> #<Date: 2001-02-03 ...>
See also jd and new.
Parses the given representation of date and time with the given template, and returns a hash of parsed elements. _strptime does not support specification of flags and width unlike strftime.
Date._strptime('2001-02-03', '%Y-%m-%d')
#=> {:year=>2001, :mon=>2, :mday=>3}
See also strptime(3) and strftime.
Parses the given representation of date and time with the given template, and creates a date object. strptime does not support specification of flags and width unlike strftime.
Date.strptime('2001-02-03', '%Y-%m-%d') #=> #<Date: 2001-02-03 ...> Date.strptime('03-02-2001', '%d-%m-%Y') #=> #<Date: 2001-02-03 ...> Date.strptime('2001-034', '%Y-%j') #=> #<Date: 2001-02-03 ...> Date.strptime('2001-W05-6', '%G-W%V-%u') #=> #<Date: 2001-02-03 ...> Date.strptime('2001 04 6', '%Y %U %w') #=> #<Date: 2001-02-03 ...> Date.strptime('2001 05 6', '%Y %W %u') #=> #<Date: 2001-02-03 ...> Date.strptime('sat3feb01', '%a%d%b%y') #=> #<Date: 2001-02-03 ...>
See also strptime(3) and strftime.
Parses the given representation of date and time, and returns a hash of parsed elements. This method does not function as a validator.
If the optional second argument is true and the detected year is in the range “00” to “99”, considers the year a 2-digit form and makes it full.
Date._parse('2001-02-03') #=> {:year=>2001, :mon=>2, :mday=>3}
Parses the given representation of date and time, and creates a date object. This method does not function as a validator.
If the optional second argument is true and the detected year is in the range “00” to “99”, considers the year a 2-digit form and makes it full.
Date.parse('2001-02-03') #=> #<Date: 2001-02-03 ...> Date.parse('20010203') #=> #<Date: 2001-02-03 ...> Date.parse('3rd Feb 2001') #=> #<Date: 2001-02-03 ...>
Returns a hash of parsed elements.
Creates a new Date object by parsing from a string according to some RFC 2616 format.
Date.httpdate('Sat, 03 Feb 2001 00:00:00 GMT') #=> #<Date: 2001-02-03 ...>
Returns the astronomical modified Julian day number. This is a fractional number, which is not adjusted by the offset.
DateTime.new(2001,2,3,4,5,6,'+7').amjd #=> (249325817/4800) DateTime.new(2001,2,2,14,5,6,'-7').amjd #=> (249325817/4800)