Results for: "to_proc"

Returns true if yield would execute a block in the current context. The iterator? form is mildly deprecated.

def try
  if block_given?
    yield
  else
    "no block"
  end
end
try                  #=> "no block"
try { "hello" }      #=> "hello"
try do "hello" end   #=> "hello"

Convert str to ISO-2022-JP

Convert str to ISO-2022-JP

Convert str to EUC-JP

Convert str to EUC-JP

Convert str to Shift_JIS

Convert str to Shift_JIS

Convert str to UTF-8

Convert str to UTF-8

Convert str to UTF-16

Convert str to UTF-16

Convert str to UTF-32

Convert str to UTF-32

Returns true if the named file is a directory, or a symlink that points at a directory, and false otherwise.

file_name can be an IO object.

File.directory?(".")

Returns true if new is newer than all old_list. Non-existent files are older than any file.

FileUtils.uptodate?('hello.o', %w(hello.c hello.h)) or \
    system 'make hello.o'

Returns true if new is newer than all old_list. Non-existent files are older than any file.

FileUtils.uptodate?('hello.o', %w(hello.c hello.h)) or \
    system 'make hello.o'

Updates modification time (mtime) and access time (atime) of file(s) in list. Files are created if they don’t exist.

FileUtils.touch 'timestamp'
FileUtils.touch Dir.glob('*.c');  system 'make'

Updates modification time (mtime) and access time (atime) of file(s) in list. Files are created if they don’t exist.

FileUtils.touch 'timestamp'
FileUtils.touch Dir.glob('*.c');  system 'make'

Returns the result of converting the serialized data in source into a Ruby object (possibly with associated subordinate objects). source may be either an instance of IO or an object that responds to to_str. If proc is specified, each object will be passed to the proc, as the object is being deserialized.

Never pass untrusted data (including user supplied input) to this method. Please see the overview for further details.

Returns a list of the private instance methods defined in mod. If the optional parameter is false, the methods of any ancestors are not included.

module Mod
  def method1()  end
  private :method1
  def method2()  end
end
Mod.instance_methods           #=> [:method2]
Mod.private_instance_methods   #=> [:method1]

Returns the Ruby source filename and line number containing first definition of constant specified. If the named constant is not found, nil is returned. If the constant is found, but its source location can not be extracted (constant is defined in C code), empty array is returned.

inherit specifies whether to lookup in mod.ancestors (true by default).

# test.rb:
class A
  C1 = 1
end

module M
  C2 = 2
end

class B < A
  include M
  C3 = 3
end

class A # continuation of A definition
end

p B.const_source_location('C3')           # => ["test.rb", 11]
p B.const_source_location('C2')           # => ["test.rb", 6]
p B.const_source_location('C1')           # => ["test.rb", 2]

p B.const_source_location('C2', false)    # => nil  -- don't lookup in ancestors

p Object.const_source_location('B')       # => ["test.rb", 9]
p Object.const_source_location('A')       # => ["test.rb", 1]  -- note it is first entry, not "continuation"

p B.const_source_location('A')            # => ["test.rb", 1]  -- because Object is in ancestors
p M.const_source_location('A')            # => ["test.rb", 1]  -- Object is not ancestor, but additionally checked for modules

p Object.const_source_location('A::C1')   # => ["test.rb", 2]  -- nesting is supported
p Object.const_source_location('String')  # => []  -- constant is defined in C code

Returns true if the named private method is defined by mod. If inherit is set, the lookup will also search mod’s ancestors. String arguments are converted to symbols.

module A
  def method1()  end
end
class B
  private
  def method2()  end
end
class C < B
  include A
  def method3()  end
end

A.method_defined? :method1                   #=> true
C.private_method_defined? "method1"          #=> false
C.private_method_defined? "method2"          #=> true
C.private_method_defined? "method2", true    #=> true
C.private_method_defined? "method2", false   #=> false
C.method_defined? "method2"                  #=> false

Makes existing class methods private. Often used to hide the default constructor new.

String arguments are converted to symbols.

class SimpleSingleton  # Not thread safe
  private_class_method :new
  def SimpleSingleton.create(*args, &block)
    @me = new(*args, &block) if ! @me
    @me
  end
end