Pushes back bytes (passed as a parameter) onto ios, such that a subsequent buffered read will return it. It is only guaranteed to support a single byte, and only if ungetbyte or ungetc has not already been called on ios since the previous read of at least a single byte from ios. However, it can support additional bytes if there is space in the internal buffer to allow for it.
f = File.new("testfile") #=> #<File:testfile> b = f.getbyte #=> 0x38 f.ungetbyte(b) #=> nil f.getbyte #=> 0x38
If given an integer, only uses the lower 8 bits of the integer as the byte to push.
f = File.new("testfile") #=> #<File:testfile> f.ungetbyte(0x102) #=> nil f.getbyte #=> 0x2
Calling this method prepends to the existing buffer, even if the method has already been called previously:
f = File.new("testfile") #=> #<File:testfile> f.ungetbyte("ab") #=> nil f.ungetbyte("cd") #=> nil f.read(5) #=> "cdab8"
Has no effect with unbuffered reads (such as IO#sysread).
Pushes back characters (passed as a parameter) onto ios, such that a subsequent buffered read will return it. It is only guaranteed to support a single byte, and only if ungetbyte or ungetc has not already been called on ios since the previous read of at least a single byte from ios. However, it can support additional bytes if there is space in the internal buffer to allow for it.
f = File.new("testfile") #=> #<File:testfile> c = f.getc #=> "8" f.ungetc(c) #=> nil f.getc #=> "8"
If given an integer, the integer must represent a valid codepoint in the external encoding of ios.
Calling this method prepends to the existing buffer, even if the method has already been called previously:
f = File.new("testfile") #=> #<File:testfile> f.ungetc("ab") #=> nil f.ungetc("cd") #=> nil f.read(5) #=> "cdab8"
Has no effect with unbuffered reads (such as IO#sysread).
Closes ios and flushes any pending writes to the operating system. The stream is unavailable for any further data operations; an IOError is raised if such an attempt is made. I/O streams are automatically closed when they are claimed by the garbage collector.
If ios is opened by IO.popen, close sets $?.
Calling this method on closed IO object is just ignored since Ruby 2.3.
Returns true if ios is completely closed (for duplex streams, both reader and writer), false otherwise.
f = File.new("testfile") f.close #=> nil f.closed? #=> true f = IO.popen("/bin/sh","r+") f.close_write #=> nil f.closed? #=> false f.close_read #=> nil f.closed? #=> true
Returns true if the underlying file descriptor of ios will be closed automatically at its finalization, otherwise false.
Sets auto-close flag.
f = open("/dev/null") IO.for_fd(f.fileno) # ... f.gets # may cause Errno::EBADF f = open("/dev/null") IO.for_fd(f.fileno).autoclose = false # ... f.gets # won't cause Errno::EBADF
Returns true if object is an element of self, false otherwise:
(1..4).include?(2) # => true (1..4).include?(5) # => false (1..4).include?(4) # => true (1...4).include?(4) # => false ('a'..'d').include?('b') # => true ('a'..'d').include?('e') # => false ('a'..'d').include?('B') # => false ('a'..'d').include?('d') # => true ('a'...'d').include?('d') # => false
If begin and end are numeric, include? behaves like cover?
(1..3).include?(1.5) # => true (1..3).cover?(1.5) # => true
But when not numeric, the two methods may differ:
('a'..'d').include?('cc') # => false ('a'..'d').cover?('cc') # => true
Related: Range#cover?.
Range#member? is an alias for Range#include?.
Returns true if the given argument is within self, false otherwise.
With non-range argument object, evaluates with <= and <.
For range self with included end value (#exclude_end? == false), evaluates thus:
self.begin <= object <= self.end
Examples:
r = (1..4) r.cover?(1) # => true r.cover?(4) # => true r.cover?(0) # => false r.cover?(5) # => false r.cover?('foo') # => false r = ('a'..'d') r.cover?('a') # => true r.cover?('d') # => true r.cover?(' ') # => false r.cover?('e') # => false r.cover?(0) # => false
For range r with excluded end value (#exclude_end? == true), evaluates thus:
r.begin <= object < r.end
Examples:
r = (1...4) r.cover?(1) # => true r.cover?(3) # => true r.cover?(0) # => false r.cover?(4) # => false r.cover?('foo') # => false r = ('a'...'d') r.cover?('a') # => true r.cover?('c') # => true r.cover?(' ') # => false r.cover?('d') # => false r.cover?(0) # => false
With range argument range, compares the first and last elements of self and range:
r = (1..4) r.cover?(1..4) # => true r.cover?(0..4) # => false r.cover?(1..5) # => false r.cover?('a'..'d') # => false r = (1...4) r.cover?(1..3) # => true r.cover?(1..4) # => false
If begin and end are numeric, cover? behaves like include?
(1..3).cover?(1.5) # => true (1..3).include?(1.5) # => true
But when not numeric, the two methods may differ:
('a'..'d').cover?('cc') # => true ('a'..'d').include?('cc') # => false
Returns false if either:
The begin value of self is larger than its end value.
An internal call to <=> returns nil; that is, the operands are not comparable.
Related: Range#include?.
Returns true if the set is a superset of the given set.
Returns true if the set and the given enumerable have at least one element in common.
Set[1, 2, 3].intersect? Set[4, 5] #=> false Set[1, 2, 3].intersect? Set[3, 4] #=> true Set[1, 2, 3].intersect? 4..5 #=> false Set[1, 2, 3].intersect? [3, 4] #=> true
Equivalent to Set#select!
In general, to_sym returns the Symbol corresponding to an object. As sym is already a symbol, self is returned in this case.
Callback invoked whenever a subclass of the current class is created.
Example:
class Foo def self.inherited(subclass) puts "New subclass: #{subclass}" end end class Bar < Foo end class Baz < Bar end
produces:
New subclass: Bar New subclass: Baz
Allocates space for a new object of class’s class and does not call initialize on the new instance. The returned object must be an instance of class.
klass = Class.new do def initialize(*args) @initialized = true end def initialized? @initialized || false end end klass.allocate.initialized? #=> false
Returns the superclass of class, or nil.
File.superclass #=> IO IO.superclass #=> Object Object.superclass #=> BasicObject class Foo; end class Bar < Foo; end Bar.superclass #=> Foo
Returns nil when the given class does not have a parent class:
BasicObject.superclass #=> nil
Returns or yields Pathname objects.
Pathname.glob("lib/i*.rb") #=> [#<Pathname:lib/ipaddr.rb>, #<Pathname:lib/irb.rb>]
See Dir.glob.
Returns the current working directory as a Pathname.
Pathname.getwd #=> #<Pathname:/home/zzak/projects/ruby>
See Dir.getwd.
Returns or yields Pathname objects.
Pathname("ruby-2.4.2").glob("R*.md") #=> [#<Pathname:ruby-2.4.2/README.md>, #<Pathname:ruby-2.4.2/README.ja.md>]
See Dir.glob. This method uses the base keyword argument of Dir.glob.
Return true if parsed source has errors.