Returns the netmask in string format e.g. 255.255.0.0
Returns true
if the log level allows entries with severity Logger::WARN to be written, false
otherwise. See Log Level.
Sets the log level to Logger::WARN. See Log Level.
Returns true
if the log level allows entries with severity Logger::ERROR to be written, false
otherwise. See Log Level.
Sets the log level to Logger::ERROR. See Log Level.
Equivalent to calling add
with severity Logger::WARN
.
Equivalent to calling add
with severity Logger::ERROR
.
Heading banner preceding summary.
Puts option summary into to
and returns to
. Yields each line if a block is given.
to
Output destination, which must have method <<. Defaults to [].
width
Width of left side, defaults to @summary_width.
max
Maximum length allowed for left side, defaults to width
- 1.
indent
Indentation, defaults to @summary_indent.
Creates an option from the given parameters params
. See Parameters for New Options.
The block, if given, is the handler for the created option. When the option is encountered during command-line parsing, the block is called with the argument given for the option, if any. See Option Handlers.
Parses command line arguments argv
in order when environment variable POSIXLY_CORRECT is set, and in permutation mode otherwise. When optional into
keyword argument is provided, the parsed option values are stored there via []=
method (so it can be Hash
, or OpenStruct
, or other similar object).
Same as parse
, but removes switches destructively. Non-option arguments remain in argv
.
Defines a new Data class. If the first argument is a string, the class is stored in Data::<name>
constant.
measure = Data.define(:amount, :unit) #=> #<Class:0x00007f70c6868498> measure.new(1, 'km') #=> #<data amount=1, unit="km"> # It you store the new class in the constant, it will # affect #inspect and will be more natural to use: Measure = Data.define(:amount, :unit) #=> Measure Measure.new(1, 'km') #=> #<data Measure amount=1, unit="km">
Note that member-less Data is acceptable and might be a useful technique for defining several homogenous data classes, like
class HTTPFetcher Response = Data.define(:body) NotFound = Data.define # ... implementation end
Now, different kinds of responses from HTTPFetcher
would have consistent representation:
#<data HTTPFetcher::Response body="<html..."> #<data HTTPFetcher::NotFound>
And are convenient to use in pattern matching:
case fetcher.get(url) in HTTPFetcher::Response(body) # process body variable in HTTPFetcher::NotFound # handle not found case end
Increases left margin after newline with indent
for line breaks added in the block.
Opens a transaction block for the store. See Transactions.
With argument read_only
as false
, the block may both read from and write to the store.
With argument read_only
as true
, the block may not include calls to transaction
, []=
, or delete
.
Raises an exception if called within a transaction block.
Returns the number of mandatory arguments. If the block is declared to take no arguments, returns 0. If the block is known to take exactly n arguments, returns n. If the block has optional arguments, returns -n-1, where n is the number of mandatory arguments, with the exception for blocks that are not lambdas and have only a finite number of optional arguments; in this latter case, returns n. Keyword arguments will be considered as a single additional argument, that argument being mandatory if any keyword argument is mandatory. A proc
with no argument declarations is the same as a block declaring ||
as its arguments.
proc {}.arity #=> 0 proc { || }.arity #=> 0 proc { |a| }.arity #=> 1 proc { |a, b| }.arity #=> 2 proc { |a, b, c| }.arity #=> 3 proc { |*a| }.arity #=> -1 proc { |a, *b| }.arity #=> -2 proc { |a, *b, c| }.arity #=> -3 proc { |x:, y:, z:0| }.arity #=> 1 proc { |*a, x:, y:0| }.arity #=> -2 proc { |a=0| }.arity #=> 0 lambda { |a=0| }.arity #=> -1 proc { |a=0, b| }.arity #=> 1 lambda { |a=0, b| }.arity #=> -2 proc { |a=0, b=0| }.arity #=> 0 lambda { |a=0, b=0| }.arity #=> -1 proc { |a, b=0| }.arity #=> 1 lambda { |a, b=0| }.arity #=> -2 proc { |(a, b), c=0| }.arity #=> 1 lambda { |(a, b), c=0| }.arity #=> -2 proc { |a, x:0, y:0| }.arity #=> 1 lambda { |a, x:0, y:0| }.arity #=> -2
Returns a curried proc. If the optional arity argument is given, it determines the number of arguments. A curried proc receives some arguments. If a sufficient number of arguments are supplied, it passes the supplied arguments to the original proc and returns the result. Otherwise, returns another curried proc that takes the rest of arguments.
The optional arity argument should be supplied when currying procs with variable arguments to determine how many arguments are needed before the proc is called.
b = proc {|x, y, z| (x||0) + (y||0) + (z||0) } p b.curry[1][2][3] #=> 6 p b.curry[1, 2][3, 4] #=> 6 p b.curry(5)[1][2][3][4][5] #=> 6 p b.curry(5)[1, 2][3, 4][5] #=> 6 p b.curry(1)[1] #=> 1 b = proc {|x, y, z, *w| (x||0) + (y||0) + (z||0) + w.inject(0, &:+) } p b.curry[1][2][3] #=> 6 p b.curry[1, 2][3, 4] #=> 10 p b.curry(5)[1][2][3][4][5] #=> 15 p b.curry(5)[1, 2][3, 4][5] #=> 15 p b.curry(1)[1] #=> 1 b = lambda {|x, y, z| (x||0) + (y||0) + (z||0) } p b.curry[1][2][3] #=> 6 p b.curry[1, 2][3, 4] #=> wrong number of arguments (given 4, expected 3) p b.curry(5) #=> wrong number of arguments (given 5, expected 3) p b.curry(1) #=> wrong number of arguments (given 1, expected 3) b = lambda {|x, y, z, *w| (x||0) + (y||0) + (z||0) + w.inject(0, &:+) } p b.curry[1][2][3] #=> 6 p b.curry[1, 2][3, 4] #=> 10 p b.curry(5)[1][2][3][4][5] #=> 15 p b.curry(5)[1, 2][3, 4][5] #=> 15 p b.curry(1) #=> wrong number of arguments (given 1, expected 3) b = proc { :foo } p b.curry[] #=> :foo
Returns a clone of this method.
class A def foo return "bar" end end m = A.new.method(:foo) m.call # => "bar" n = m.clone.call # => "bar"
Returns a curried proc based on the method. When the proc is called with a number of arguments that is lower than the method’s arity, then another curried proc is returned. Only when enough arguments have been supplied to satisfy the method signature, will the method actually be called.
The optional arity argument should be supplied when currying methods with variable arguments to determine how many arguments are needed before the method is called.
def foo(a,b,c) [a, b, c] end proc = self.method(:foo).curry proc2 = proc.call(1, 2) #=> #<Proc> proc2.call(3) #=> [1,2,3] def vararg(*args) args end proc = self.method(:vararg).curry(4) proc2 = proc.call(:x) #=> #<Proc> proc3 = proc2.call(:y, :z) #=> #<Proc> proc3.call(:a) #=> [:x, :y, :z, :a]
Returns an indication of the number of arguments accepted by a method. Returns a nonnegative integer for methods that take a fixed number of arguments. For Ruby methods that take a variable number of arguments, returns -n-1, where n is the number of required arguments. Keyword arguments will be considered as a single additional argument, that argument being mandatory if any keyword argument is mandatory. For methods written in C, returns -1 if the call takes a variable number of arguments.
class C def one; end def two(a); end def three(*a); end def four(a, b); end def five(a, b, *c); end def six(a, b, *c, &d); end def seven(a, b, x:0); end def eight(x:, y:); end def nine(x:, y:, **z); end def ten(*a, x:, y:); end end c = C.new c.method(:one).arity #=> 0 c.method(:two).arity #=> 1 c.method(:three).arity #=> -1 c.method(:four).arity #=> 2 c.method(:five).arity #=> -3 c.method(:six).arity #=> -3 c.method(:seven).arity #=> -3 c.method(:eight).arity #=> 1 c.method(:nine).arity #=> 1 c.method(:ten).arity #=> -2 "cat".method(:size).arity #=> 0 "cat".method(:replace).arity #=> 1 "cat".method(:squeeze).arity #=> -1 "cat".method(:count).arity #=> -1
Returns the class or module on which this method is defined. In other words,
meth.owner.instance_methods(false).include?(meth.name) # => true
holds as long as the method is not removed/undefined/replaced, (with private_instance_methods instead of instance_methods if the method is private).
See also Method#receiver
.
(1..3).method(:map).owner #=> Enumerable
Returns a clone of this method.
class A def foo return "bar" end end m = A.new.method(:foo) m.call # => "bar" n = m.clone.call # => "bar"