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.
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.
Converts pattern to a Regexp (if it isn’t already one), then invokes its match method on str. If the second parameter is present, it specifies the position in the string to begin the search.
'hello'.match('(.)\1') #=> #<MatchData "ll" 1:"l"> 'hello'.match('(.)\1')[0] #=> "ll" 'hello'.match(/(.)\1/)[0] #=> "ll" 'hello'.match('xx') #=> nil
If a block is given, invoke the block with MatchData if match succeed, so that you can write
str.match(pat) {|m| ...}
instead of
if m = str.match(pat) ... end
The return value is a value from block execution in this case.