@!visibility private @see DependencyGraph#detach_vertex_named
Obtains a lock, runs the block, and releases the lock when the block completes. See the example under Mutex
.
Passes each character in str to the given block, or returns an enumerator if no block is given.
"hello".each_char {|c| print c, ' ' }
produces:
h e l l o
Calls the given block once for each character in ios, passing the character as an argument. The stream must be opened for reading or an IOError
will be raised.
If no block is given, an enumerator is returned instead.
f = File.new("testfile") f.each_char {|c| print c, ' ' } #=> #<File:testfile>
Iterates over the children of the directory (files and subdirectories, not recursive).
It yields Pathname
object for each child.
By default, the yielded 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.
Pathname("/usr/local").each_child {|f| p f } #=> #<Pathname:/usr/local/share> # #<Pathname:/usr/local/bin> # #<Pathname:/usr/local/games> # #<Pathname:/usr/local/lib> # #<Pathname:/usr/local/include> # #<Pathname:/usr/local/sbin> # #<Pathname:/usr/local/src> # #<Pathname:/usr/local/man> Pathname("/usr/local").each_child(false) {|f| p f } #=> #<Pathname:share> # #<Pathname:bin> # #<Pathname:games> # #<Pathname:lib> # #<Pathname:include> # #<Pathname:sbin> # #<Pathname:src> # #<Pathname:man>
Note that the results never contain the entries .
and ..
in the directory because they are not children.
Iterates over each character of each file in ARGF
.
This method allows you to treat the files supplied on the command line as a single file consisting of the concatenation of each named file. After the last character of the first file has been returned, the first character of the second file is returned. The ARGF.filename
method can be used to determine the name of the file in which the current character appears.
If no block is given, an enumerator is returned instead.
Enters exclusive section and executes the block. Leaves the exclusive section automatically when the block exits. See example under MonitorMixin
.
See Mutex#synchronize
Should be implemented by a extended class.
tsort_each_child
is used to iterate for child nodes of node.
See Zlib::GzipReader
documentation for a description.
check the scheme v
component against the URI::Parser
Regexp
for :SCHEME
Verifies each certificate in chain
has signed the following certificate and is valid for the given time
.
Tries to return the element at position index
, but throws an IndexError
exception if the referenced index
lies outside of the array bounds. This error can be prevented by supplying a second argument, which will act as a default
value.
Alternatively, if a block is given it will only be executed when an invalid index
is referenced.
Negative values of index
count from the end of the array.
a = [ 11, 22, 33, 44 ] a.fetch(1) #=> 22 a.fetch(-1) #=> 44 a.fetch(4, 'cat') #=> "cat" a.fetch(100) { |i| puts "#{i} is out of bounds" } #=> "100 is out of bounds"
Calls the given block once for each element in self
, passing that element as a parameter. Returns the array itself.
If no block is given, an Enumerator
is returned.
a = [ "a", "b", "c" ] a.each {|x| print x, " -- " }
produces:
a -- b -- c --
Calls the given block for each element n
times or forever if nil
is given.
Does nothing if a non-positive number is given or the array is empty.
Returns nil
if the loop has finished without getting interrupted.
If no block is given, an Enumerator
is returned instead.
a = ["a", "b", "c"] a.cycle { |x| puts x } # print, a, b, c, a, b, c,.. forever. a.cycle(2) { |x| puts x } # print, a, b, c, a, b, c.
By using binary search, finds a value from this array which meets the given condition in O(log n) where n is the size of the array.
You can use this method in two use cases: a find-minimum mode and a find-any mode. In either case, the elements of the array must be monotone (or sorted) with respect to the block.
In find-minimum mode (this is a good choice for typical use case), the block must return true or false, and there must be an index i (0 <= i <= ary.size) so that:
the block returns false for any element whose index is less than i, and
the block returns true for any element whose index is greater than or equal to i.
This method returns the i-th element. If i is equal to ary.size, it returns nil.
ary = [0, 4, 7, 10, 12] ary.bsearch {|x| x >= 4 } #=> 4 ary.bsearch {|x| x >= 6 } #=> 7 ary.bsearch {|x| x >= -1 } #=> 0 ary.bsearch {|x| x >= 100 } #=> nil
In find-any mode (this behaves like libc’s bsearch(3)), the block must return a number, and there must be two indices i and j (0 <= i <= j <= ary.size) so that:
the block returns a positive number for ary if 0 <= k < i,
the block returns zero for ary if i <= k < j, and
the block returns a negative number for ary if j <= k < ary.size.
Under this condition, this method returns any element whose index is within i…j. If i is equal to j (i.e., there is no element that satisfies the block), this method returns nil.
ary = [0, 4, 7, 10, 12] # try to find v such that 4 <= v < 8 ary.bsearch {|x| 1 - x / 4 } #=> 4 or 7 # try to find v such that 8 <= v < 10 ary.bsearch {|x| 4 - x / 2 } #=> nil
You must not mix the two modes at a time; the block must always return either true/false, or always return a number. It is undefined which value is actually picked up at each iteration.