Returns true if the stream is associated with a terminal device (tty), false otherwise:
f = File.new('t.txt').isatty #=> false f.close f = File.new('/dev/tty').isatty #=> true f.close
Sets the stream’s data mode as binary (see Data Mode).
A stream’s data mode may not be changed from binary to text.
Returns true if the stream is on binary mode, false otherwise. See Data Mode.
Returns the path associated with the IO, or nil if there is no path associated with the IO. It is not guaranteed that the path exists on the filesystem.
$stdin.path # => "<STDIN>" File.open("testfile") {|f| f.path} # => "testfile"
With a block given, passes each element of self to the block:
a = [] (1..4).each {|element| a.push(element) } # => 1..4 a # => [1, 2, 3, 4]
Raises an exception unless self.first.respond_to?(:succ).
With no block given, returns an enumerator.
Returns the maximum value in self, using method <=> or a given block for comparison.
With no argument and no block given, returns the maximum-valued element of self.
(1..4).max # => 4 ('a'..'d').max # => "d" (-4..-1).max # => -1
With non-negative integer argument n given, and no block given, returns the n maximum-valued elements of self in an array:
(1..4).max(2) # => [4, 3] ('a'..'d').max(2) # => ["d", "c"] (-4..-1).max(2) # => [-1, -2] (1..4).max(50) # => [4, 3, 2, 1]
If a block is given, it is called:
First, with the first two element of self.
Then, sequentially, with the so-far maximum value and the next element of self.
To illustrate:
(1..4).max {|a, b| p [a, b]; a <=> b } # => 4
Output:
[2, 1] [3, 2] [4, 3]
With no argument and a block given, returns the return value of the last call to the block:
(1..4).max {|a, b| -(a <=> b) } # => 1
With non-negative integer argument n given, and a block given, returns the return values of the last n calls to the block in an array:
(1..4).max(2) {|a, b| -(a <=> b) } # => [1, 2] (1..4).max(50) {|a, b| -(a <=> b) } # => [1, 2, 3, 4]
Returns an empty array if n is zero:
(1..4).max(0) # => [] (1..4).max(0) {|a, b| -(a <=> b) } # => []
Returns nil or an empty array if:
The begin value of the range is larger than the end value:
(4..1).max # => nil (4..1).max(2) # => [] (4..1).max {|a, b| -(a <=> b) } # => nil (4..1).max(2) {|a, b| -(a <=> b) } # => []
The begin value of an exclusive range is equal to the end value:
(1...1).max # => nil (1...1).max(2) # => [] (1...1).max {|a, b| -(a <=> b) } # => nil (1...1).max(2) {|a, b| -(a <=> b) } # => []
Raises an exception if either:
self is a endless range: (1..).
A block is given and self is a beginless range.
Related: Range#min, Range#minmax.
Returns the numerator.
Rational(7).numerator #=> 7 Rational(7, 1).numerator #=> 7 Rational(9, -4).numerator #=> -9 Rational(-2, -10).numerator #=> 1
Returns the denominator (always positive).
Rational(7).denominator #=> 1 Rational(7, 1).denominator #=> 1 Rational(9, -4).denominator #=> 4 Rational(-2, -10).denominator #=> 5
Returns true if rat is less than 0.
Returns rat truncated (toward zero) to a precision of ndigits decimal digits (default: 0).
When the precision is negative, the returned value is an integer with at least ndigits.abs trailing zeros.
Returns a rational when ndigits is positive, otherwise returns an integer.
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 Rational('-123.456').truncate(+1).to_f #=> -123.4 Rational('-123.456').truncate(-1) #=> -120
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 set that is a copy of the set, flattening each containing set recursively.
Equivalent to Set#flatten, but replaces the receiver with the result in place. Returns nil if no modifications were made.
Calls the given block once for each element in the set, passing the element as parameter. Returns an enumerator if no block is given.
Calls the given block with the value of each member; returns self:
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.each {|value| p value }
Output:
"Joe Smith" "123 Maple, Anytown NC" 12345
Returns an Enumerator if no block is given.
Related: each_pair.
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 clean pathname of self with consecutive slashes and useless dots removed. The filesystem is not accessed.
If consider_symlink is true, then a more conservative algorithm is used to avoid breaking symbolic linkages. This may retain more .. entries than absolutely necessary, but without accessing the filesystem, this can’t be avoided.
See Pathname#realpath.
The opposite of Pathname#absolute?
It returns false if the pathname begins with a slash.
p = Pathname.new('/im/sure') p.relative? #=> false p = Pathname.new('not/so/sure') p.relative? #=> true
Returns the children of the directory (files and subdirectories, not recursive) as an array of Pathname objects.
By default, the returned pathnames will have enough information to access the files. If you set with_directory to false, then the returned pathnames will contain the filename only.
For example:
pn = Pathname("/usr/lib/ruby/1.8")
pn.children
# -> [ Pathname:/usr/lib/ruby/1.8/English.rb,
Pathname:/usr/lib/ruby/1.8/Env.rb,
Pathname:/usr/lib/ruby/1.8/abbrev.rb, ... ]
pn.children(false)
# -> [ Pathname:English.rb, Pathname:Env.rb, Pathname:abbrev.rb, ... ]
Note that the results never contain the entries . and .. in the directory because they are not children.
Creates a full path, including any intermediate directories that don’t yet exist.
See FileUtils.mkpath and FileUtils.mkdir_p
Returns the real (absolute) pathname for self in the actual filesystem.
Does not contain symlinks or useless dots, .. and ..
All components of the pathname must exist when this method is called.