Installs the gem and returns a loaded Gem::Specification for the installed gem.
The gem will be installed with the following structure:
@gem_home/ cache/<gem-version>.gem #=> a cached copy of the installed gem gems/<gem-version>/... #=> extracted files specifications/<gem-version>.gemspec #=> the Gem::Specification
Installs gems for this RequestSet using the Gem::Installer options.
If a block is given an activation request and installer are yielded. The installer will be nil if a gem matching the request was already installed.
Performs the uninstall of the gem. This removes the spec, the Gem directory, and the cached .gem file.
Create a new CallTargetNode node
Check if gem name version version is installed.
Returns true if all elements of self meet a given criterion.
If self has no element, returns true and argument or block are not used.
With no block given and no argument, returns true if self contains only truthy elements, false otherwise:
[0, 1, :foo].all? # => true [0, nil, 2].all? # => false [].all? # => true
With a block given and no argument, calls the block with each element in self; returns true if the block returns only truthy values, false otherwise:
[0, 1, 2].all? { |element| element < 3 } # => true [0, 1, 2].all? { |element| element < 2 } # => false
If argument obj is given, returns true if obj.=== every element, false otherwise:
['food', 'fool', 'foot'].all?(/foo/) # => true ['food', 'drink'].all?(/bar/) # => false [].all?(/foo/) # => true [0, 0, 0].all?(0) # => true [0, 1, 2].all?(1) # => false
Related: Enumerable#all?
Returns true if all bits that are set (=1) in mask are also set in self; returns false otherwise.
Example values:
0b1010101 self
0b1010100 mask
0b1010100 self & mask
true self.allbits?(mask)
0b1010100 self
0b1010101 mask
0b1010100 self & mask
false self.allbits?(mask)
Related: Integer#anybits?, Integer#nobits?.
Returns a string containing the characters in self; the first character is upcased; the remaining characters are downcased:
s = 'hello World!' # => "hello World!" s.capitalize # => "Hello world!"
The casing may be affected by the given options; see Case Mapping.
Related: String#capitalize!.
Upcases the first character in self; downcases the remaining characters; returns self if any changes were made, nil otherwise:
s = 'hello World!' # => "hello World!" s.capitalize! # => "Hello world!" s # => "Hello world!" s.capitalize! # => nil
The casing may be affected by the given options; see Case Mapping.
Related: String#capitalize.
Invokes the continuation. The program continues from the end of the callcc block. If no arguments are given, the original callcc returns nil. If one argument is given, callcc returns it. Otherwise, an array containing args is returned.
callcc {|cont| cont.call } #=> nil callcc {|cont| cont.call 1 } #=> 1 callcc {|cont| cont.call 1, 2, 3 } #=> [1, 2, 3]
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 true if the log level allows entries with severity Logger::FATAL to be written, false otherwise. See Log Level.
Sets the log level to Logger::FATAL. See Log Level.
Equivalent to calling add with severity Logger::FATAL.
Invokes the block, setting the block’s parameters to the values in params using something close to method calling semantics. Returns the value of the last expression evaluated in the block.
a_proc = Proc.new {|scalar, *values| values.map {|value| value*scalar } } a_proc.call(9, 1, 2, 3) #=> [9, 18, 27] a_proc[9, 1, 2, 3] #=> [9, 18, 27] a_proc.(9, 1, 2, 3) #=> [9, 18, 27] a_proc.yield(9, 1, 2, 3) #=> [9, 18, 27]
Note that prc.() invokes prc.call() with the parameters given. It’s syntactic sugar to hide “call”.
For procs created using lambda or ->() an error is generated if the wrong number of parameters are passed to the proc. For procs created using Proc.new or Kernel.proc, extra parameters are silently discarded and missing parameters are set to nil.
a_proc = proc {|a,b| [a,b] } a_proc.call(1) #=> [1, nil] a_proc = lambda {|a,b| [a,b] } a_proc.call(1) # ArgumentError: wrong number of arguments (given 1, expected 2)
See also Proc#lambda?.
Invokes the meth with the specified arguments, returning the method’s return value.
m = 12.method("+") m.call(3) #=> 15 m.call(20) #=> 32
Generates a Continuation object, which it passes to the associated block. You need to require 'continuation' before using this method. Performing a cont.call will cause the callcc to return (as will falling through the end of the block). The value returned by the callcc is the value of the block, or the value passed to cont.call. See class Continuation for more details. Also see Kernel#throw for an alternative mechanism for unwinding a call stack.
Returns the called name of the current method as a Symbol. If called outside of a method, it returns nil.
Invokes Posix system call syscall(2), which calls a specified function.
Calls the operating system function identified by integer_callno; returns the result of the function or raises SystemCallError if it failed. The effect of the call is platform-dependent. The arguments and returned value are platform-dependent.
For each of arguments: if it is an integer, it is passed directly; if it is a string, it is interpreted as a binary sequence of bytes. There may be as many as nine such arguments.
Arguments integer_callno and argument, as well as the returned value, are platform-dependent.
Note: Method syscall is essentially unsafe and unportable. The DL (Fiddle) library is preferred for safer and a bit more portable programming.
Not implemented on all platforms.
Returns the current execution stack—an array containing strings in the form file:line or file:line: in `method'.
The optional start parameter determines the number of initial stack entries to omit from the top of the stack.
A second optional length parameter can be used to limit how many entries are returned from the stack.
Returns nil if start is greater than the size of current execution stack.
Optionally you can pass a range, which will return an array containing the entries within the specified range.
def a(skip) caller(skip) end def b(skip) a(skip) end def c(skip) b(skip) end c(0) #=> ["prog:2:in `a'", "prog:5:in `b'", "prog:8:in `c'", "prog:10:in `<main>'"] c(1) #=> ["prog:5:in `b'", "prog:8:in `c'", "prog:11:in `<main>'"] c(2) #=> ["prog:8:in `c'", "prog:12:in `<main>'"] c(3) #=> ["prog:13:in `<main>'"] c(4) #=> [] c(5) #=> nil
Returns whether every element meets a given criterion.
If self has no element, returns true and argument or block are not used.
With no argument and no block, returns whether every element is truthy:
(1..4).all? # => true %w[a b c d].all? # => true [1, 2, nil].all? # => false ['a','b', false].all? # => false [].all? # => true
With argument pattern and no block, returns whether for each element element, pattern === element:
(1..4).all?(Integer) # => true (1..4).all?(Numeric) # => true (1..4).all?(Float) # => false %w[bar baz bat bam].all?(/ba/) # => true %w[bar baz bat bam].all?(/bar/) # => false %w[bar baz bat bam].all?('ba') # => false {foo: 0, bar: 1, baz: 2}.all?(Array) # => true {foo: 0, bar: 1, baz: 2}.all?(Hash) # => false [].all?(Integer) # => true
With a block given, returns whether the block returns a truthy value for every element:
(1..4).all? {|element| element < 5 } # => true (1..4).all? {|element| element < 4 } # => false {foo: 0, bar: 1, baz: 2}.all? {|key, value| value < 3 } # => true {foo: 0, bar: 1, baz: 2}.all? {|key, value| value < 2 } # => false
Allocate size bytes of memory and return the integer memory address for the allocated memory.
Change the size of the memory allocated at the memory location addr to size bytes. Returns the memory address of the reallocated memory, which may be different than the address passed in.