Returns the index of the first object in ary such that the object is == to obj.
If a block is given instead of an argument, returns the index of the first object for which the block returns true. Returns nil if no match is found.
See also Array#rindex.
An Enumerator is returned if neither a block nor argument is given.
a = [ "a", "b", "c" ] a.index("b") #=> 1 a.index("z") #=> nil a.index { |x| x == "b" } #=> 1
Invoked when a reference is made to an undefined constant in mod. It is passed a symbol for the undefined constant, and returns a value to be used for that constant. The following code is an example of the same:
def Foo.const_missing(name) name # return the constant name as Symbol end Foo::UNDEFINED_CONST #=> :UNDEFINED_CONST: symbol returned
In the next example when a reference is made to an undefined constant, it attempts to load a file whose name is the lowercase version of the constant (thus class Fred is assumed to be in file fred.rb). If found, it returns the loaded class. It therefore implements an autoload feature similar to Kernel#autoload and Module#autoload.
def Object.const_missing(name) @looked_for ||= {} str_name = name.to_s raise "Class not found: #{name}" if @looked_for[str_name] @looked_for[str_name] = 1 file = str_name.downcase require file klass = const_get(name) return klass if klass raise "Class not found: #{name}" end
Returns the Encoding of the internal string if conversion is specified. Otherwise returns nil.
creates an Addrinfo object from the arguments.
The arguments are interpreted as similar to self.
Addrinfo.tcp("0.0.0.0", 4649).family_addrinfo("www.ruby-lang.org", 80) #=> #<Addrinfo: 221.186.184.68:80 TCP (www.ruby-lang.org:80)> Addrinfo.unix("/tmp/sock").family_addrinfo("/tmp/sock2") #=> #<Addrinfo: /tmp/sock2 SOCK_STREAM>
Returns the Encoding of the internal string if conversion is specified. Otherwise returns nil.
Calls WIN32OLE#invoke method.
Returns the method kind string. The string is “UNKNOWN” or “PROPERTY” or “PROPERTY” or “PROPERTYGET” or “PROPERTYPUT” or “PROPERTYPPUTREF” or “FUNC”.
tobj = WIN32OLE_TYPE.new('Microsoft Excel 9.0 Object Library', 'Workbooks') method = WIN32OLE_METHOD.new(tobj, 'Add') puts method.invoke_kind # => "FUNC"
Returns value specified by the member name of VT_RECORD OLE variable. Or sets value specified by the member name of VT_RECORD OLE variable. If the member name is not correct, KeyError exception is raised.
If COM server in VB.NET ComServer project is the following:
Imports System.Runtime.InteropServices
Public Class ComClass
Public Structure Book
<MarshalAs(UnmanagedType.BStr)> _
Public title As String
Public cost As Integer
End Structure
End Class
Then getting/setting value from Ruby is as the following:
obj = WIN32OLE.new('ComServer.ComClass') book = WIN32OLE_RECORD.new('Book', obj) book.title # => nil ( book.method_missing(:title) is invoked. ) book.title = "Ruby" # ( book.method_missing(:title=, "Ruby") is invoked. )
Returns minor version.
tobj = WIN32OLE_TYPE.new('Microsoft Word 10.0 Object Library', 'Documents') puts tobj.minor_version # => 2
Returns the type library minor version.
tlib = WIN32OLE_TYPELIB.new('Microsoft Excel 9.0 Object Library') puts tlib.minor_version # -> 3
Invoked by Ruby when obj is sent a message it cannot handle. symbol is the symbol for the method called, and args are any arguments that were passed to it. By default, the interpreter raises an error when this method is called. However, it is possible to override the method to provide more dynamic behavior. If it is decided that a particular method should not be handled, then super should be called, so that ancestors can pick up the missing method. The example below creates a class Roman, which responds to methods with names consisting of roman numerals, returning the corresponding integer values.
class Roman def roman_to_int(str) # ... end def method_missing(methId) str = methId.id2name roman_to_int(str) end end r = Roman.new r.iv #=> 4 r.xxiii #=> 23 r.mm #=> 2000
Returns the internal encoding for strings read from ARGF as an Encoding object.
If ARGF.set_encoding has been called with two encoding names, the second is returned. Otherwise, if Encoding.default_external has been set, that value is returned. Failing that, if a default external encoding was specified on the command-line, that value is used. If the encoding is unknown, nil is returned.
Handles the magic of delegation through _getobj_.
Returns the submatrix obtained by deleting the specified row and column.
Matrix.diagonal(9, 5, -3, 4).first_minor(1, 2)
=> 9 0 0
0 0 0
0 0 4
Private. Use Matrix#determinant
Returns the determinant of the matrix, using Bareiss’ multistep integer-preserving gaussian elimination. It has the same computational cost order O(n^3) as standard Gaussian elimination. Intermediate results are fraction free and of lower complexity. A matrix of Integers will have thus intermediate results that are also Integers, with smaller bignums (if any), while a matrix of Float will usually have intermediate results with better precision.
Outputs obj to out like PP.pp but with no indent and newline.
PP.singleline_pp returns out.
Returns whether or not the asynchronous queue is empty.
Since Thread::handle_interrupt can be used to defer asynchronous events, this method can be used to determine if there are any deferred events.
If you find this method returns true, then you may finish :never blocks.
For example, the following method processes deferred asynchronous events immediately.
def Thread.kick_interrupt_immediately Thread.handle_interrupt(Object => :immediate) { Thread.pass } end
If error is given, then check only for error type deferred events.
th = Thread.new{
Thread.handle_interrupt(RuntimeError => :on_blocking){
while true
...
# reach safe point to invoke interrupt
if Thread.pending_interrupt?
Thread.handle_interrupt(Object => :immediate){}
end
...
end
}
}
...
th.raise # stop thread
This example can also be written as the following, which you should use to avoid asynchronous interrupts.
flag = true
th = Thread.new{
Thread.handle_interrupt(RuntimeError => :on_blocking){
while true
...
# reach safe point to invoke interrupt
break if flag == false
...
end
}
}
...
flag = false # stop thread
Returns whether or not the asynchronous queue is empty for the target thread.
If error is given, then check only for error type deferred events.
See ::pending_interrupt? for more information.
Compares each entry in enum with value or passes to block. Returns the index for the first for which the evaluated value is non-false. If no object matches, returns nil
If neither block nor argument is given, an enumerator is returned instead.
(1..10).find_index { |i| i % 5 == 0 and i % 7 == 0 } #=> nil (1..100).find_index { |i| i % 5 == 0 and i % 7 == 0 } #=> 34 (1..100).find_index(50) #=> 49
Returns the object in enum that gives the minimum value from the given block.
If no block is given, an enumerator is returned instead.
a = %w(albatross dog horse) a.min_by { |x| x.length } #=> "dog"
If the n argument is given, minimum n elements are returned as an array. These n elements are sorted by the value from the given block.
a = %w[albatross dog horse] p a.min_by(2) {|x| x.length } #=> ["dog", "horse"]