An action that modifies a {DependencyGraph} that is reversible. @abstract
A specific resolution from a given {Resolver}
Delegates
all {Gem::Resolver::Molinillo::ResolutionState} methods to a ‘#state` property.
Delegates
all {Gem::Resolver::Molinillo::SpecificationProvider} methods to a ‘#specification_provider` property.
An error caused by attempting to fulfil a dependency that was circular
@note This exception will be thrown if and only if a {Vertex} is added to a
{DependencyGraph} that has a {DependencyGraph::Vertex#path_to?} an existing {DependencyGraph::Vertex}
A state that encapsulates a single possibility to fulfill the given {#requirement}
@!visibility private (see DependencyGraph#add_edge_no_circular
)
@!visibility private @see DependencyGraph#detach_vertex_named
A vertex in a {DependencyGraph} that encapsulates a {#name} and a {#payload}
Searches sep or pattern (regexp) in the string from the end of the string, and returns the part before it, the match, and the part after it. If it is not found, returns two empty strings and str.
"hello".rpartition("l") #=> ["hel", "l", "o"] "hello".rpartition("x") #=> ["", "", "hello"] "hello".rpartition(/.l/) #=> ["he", "ll", "o"]
The match from the end means starting at the possible last position, not the last of longest matches.
"hello".rpartition(/l+/) #=> ["hel", "l", "o"]
To partition at the last longest match, needs to combine with negative lookbehind.
"hello".rpartition(/(?<!l)l+/) #=> ["he", "ll", "o"]
Or String#partition
with negative lookforward.
"hello".partition(/l+(?!.*l)/) #=> ["he", "ll", "o"]
Returns garbage collector generation for the given object
.
class B include ObjectSpace def foo trace_object_allocations do obj = Object.new p "Generation is #{allocation_generation(obj)}" end end end B.new.foo #=> "Generation is 3"
See ::trace_object_allocations
for more information and examples.
Reads at most maxlen bytes from the I/O stream. It blocks only if ios has no data immediately available. It doesn’t block if some data available.
If the optional outbuf argument is present, it must reference a String
, which will receive the data. The outbuf will contain only the received data after the method call even if it is not empty at the beginning.
It raises EOFError
on end of file.
readpartial is designed for streams such as pipe, socket, tty, etc. It blocks only when no data immediately available. This means that it blocks only when following all conditions hold.
the byte buffer in the IO
object is empty.
the content of the stream is empty.
the stream is not reached to EOF.
When readpartial blocks, it waits data or EOF on the stream. If some data is reached, readpartial returns with the data. If EOF is reached, readpartial raises EOFError
.
When readpartial doesn’t blocks, it returns or raises immediately. If the byte buffer is not empty, it returns the data in the buffer. Otherwise if the stream has some content, it returns the data in the stream. Otherwise if the stream is reached to EOF, it raises EOFError
.
r, w = IO.pipe # buffer pipe content w << "abc" # "" "abc". r.readpartial(4096) #=> "abc" "" "" r.readpartial(4096) # blocks because buffer and pipe is empty. r, w = IO.pipe # buffer pipe content w << "abc" # "" "abc" w.close # "" "abc" EOF r.readpartial(4096) #=> "abc" "" EOF r.readpartial(4096) # raises EOFError r, w = IO.pipe # buffer pipe content w << "abc\ndef\n" # "" "abc\ndef\n" r.gets #=> "abc\n" "def\n" "" w << "ghi\n" # "def\n" "ghi\n" r.readpartial(4096) #=> "def\n" "" "ghi\n" r.readpartial(4096) #=> "ghi\n" "" ""
Note that readpartial behaves similar to sysread. The differences are:
If the byte buffer is not empty, read from the byte buffer instead of “sysread for buffered IO
(IOError
)”.
It doesn’t cause Errno::EWOULDBLOCK and Errno::EINTR. When readpartial meets EWOULDBLOCK and EINTR by read system call, readpartial retry the system call.
The latter means that readpartial is nonblocking-flag insensitive. It blocks on the situation IO#sysread
causes Errno::EWOULDBLOCK as if the fd is blocking mode.
Reads at most maxlen bytes from the ARGF
stream.
If the optional outbuf argument is present, it must reference a String
, which will receive the data. The outbuf will contain only the received data after the method call even if it is not empty at the beginning.
It raises EOFError
on end of ARGF
stream. Since ARGF
stream is a concatenation of multiple files, internally EOF is occur for each file. ARGF.readpartial
returns empty strings for EOFs except the last one and raises EOFError
for the last one.
The standard configuration object for gems.
Use the given configuration object (which implements the ConfigFile
protocol) as the standard configuration object.
Returns a new Array containing each element found both in self
and in all of the given Arrays other_arrays
; duplicates are omitted; items are compared using eql?
:
[0, 1, 2, 3].intersection([0, 1, 2], [0, 1, 3]) # => [0, 1] [0, 0, 1, 1, 2, 3].intersection([0, 1, 2], [0, 1, 3]) # => [0, 1]
Preserves order from self
:
[0, 1, 2].intersection([2, 1, 0]) # => [0, 1, 2]
Returns a copy of self
if no arguments given.
Related: Array#&
.
When invoked with a block, yield all permutations of elements of self
; returns self
. The order of permutations is indeterminate.
When a block and an in-range positive Integer argument n
(0 < n <= self.size
) are given, calls the block with all n
-tuple permutations of self
.
Example:
a = [0, 1, 2] a.permutation(2) {|permutation| p permutation }
Output:
[0, 1] [0, 2] [1, 0] [1, 2] [2, 0] [2, 1]
Another example:
a = [0, 1, 2] a.permutation(3) {|permutation| p permutation }
Output:
[0, 1, 2] [0, 2, 1] [1, 0, 2] [1, 2, 0] [2, 0, 1] [2, 1, 0]
When n
is zero, calls the block once with a new empty Array:
a = [0, 1, 2] a.permutation(0) {|permutation| p permutation }
Output:
[]
When n
is out of range (negative or larger than self.size
), does not call the block:
a = [0, 1, 2] a.permutation(-1) {|permutation| fail 'Cannot happen' } a.permutation(4) {|permutation| fail 'Cannot happen' }
When a block given but no argument, behaves the same as a.permutation(a.size)
:
a = [0, 1, 2] a.permutation {|permutation| p permutation }
Output:
[0, 1, 2] [0, 2, 1] [1, 0, 2] [1, 2, 0] [2, 0, 1] [2, 1, 0]
Returns a new Enumerator if no block given:
a = [0, 1, 2] a.permutation # => #<Enumerator: [0, 1, 2]:permutation> a.permutation(2) # => #<Enumerator: [0, 1, 2]:permutation(2)>
Calls the block, if given, with combinations of elements of self
; returns self
. The order of combinations is indeterminate.
When a block and an in-range positive Integer argument n
(0 < n <= self.size
) are given, calls the block with all n
-tuple combinations of self
.
Example:
a = [0, 1, 2] a.combination(2) {|combination| p combination }
Output:
[0, 1] [0, 2] [1, 2]
Another example:
a = [0, 1, 2] a.combination(3) {|combination| p combination }
Output:
[0, 1, 2]
When n
is zero, calls the block once with a new empty Array:
a = [0, 1, 2] a1 = a.combination(0) {|combination| p combination }
Output:
[]
When n
is out of range (negative or larger than self.size
), does not call the block:
a = [0, 1, 2] a.combination(-1) {|combination| fail 'Cannot happen' } a.combination(4) {|combination| fail 'Cannot happen' }
Returns a new Enumerator if no block given:
a = [0, 1, 2] a.combination(2) # => #<Enumerator: [0, 1, 2]:combination(2)>
Returns the value as a rational. The optional argument eps
is always ignored.
Returns the value as a rational if possible (the imaginary part should be exactly zero).
Complex(1.0/3, 0).rationalize #=> (1/3) Complex(1, 0.0).rationalize # RangeError Complex(1, 2).rationalize # RangeError
See to_r.