Returns true
if file_name
is an absolute path, and false
otherwise.
File.absolute_path?("c:/foo") #=> false (on Linux), true (on Windows)
Returns true
if the named file is readable by the real user and group id of this process. See access(3).
Note that some OS-level security features may cause this to return true even though the file is not readable by the real user/group.
If file_name is readable by others, returns an integer representing the file permission bits of file_name. Returns nil
otherwise. The meaning of the bits is platform dependent; on Unix systems, see stat(2)
.
file_name can be an IO
object.
File.world_readable?("/etc/passwd") #=> 420 m = File.world_readable?("/etc/passwd") sprintf("%o", m) #=> "644"
Returns true
if the named file is writable by the real user and group id of this process. See access(3).
Note that some OS-level security features may cause this to return true even though the file is not writable by the real user/group.
If file_name is writable by others, returns an integer representing the file permission bits of file_name. Returns nil
otherwise. The meaning of the bits is platform dependent; on Unix systems, see stat(2)
.
file_name can be an IO
object.
File.world_writable?("/tmp") #=> 511 m = File.world_writable?("/tmp") sprintf("%o", m) #=> "777"
Returns true
if the named file is executable by the real user and group id of this process. See access(3).
Windows does not support execute permissions separately from read permissions. On Windows, a file is only considered executable if it ends in .bat, .cmd, .com, or .exe.
Note that some OS-level security features may cause this to return true even though the file is not executable by the real user/group.
Returns whether ASCII-compatible or not.
Encoding::UTF_8.ascii_compatible? #=> true Encoding::UTF_16BE.ascii_compatible? #=> false
Returns the list of private methods accessible to obj. If the all parameter is set to false
, only those methods in the receiver will be listed.
Returns an array of instance variable names for the receiver. Note that simply defining an accessor does not create the corresponding instance variable.
class Fred attr_accessor :a1 def initialize @iv = 3 end end Fred.new.instance_variables #=> [:@iv]
Returns true
if obj is an instance of the given class. See also Object#kind_of?
.
class A; end class B < A; end class C < B; end b = B.new b.instance_of? A #=> false b.instance_of? B #=> true b.instance_of? C #=> false
Processes a string returned by message
.
It may add the class name of the exception to the end of the first line. Also, when highlight
keyword is true, it adds ANSI escape sequences to make the message bold.
If you override this method, it must be tolerant for unknown keyword arguments. All keyword arguments passed to full_message
are delegated to this method.
This method is overridden by did_you_mean and error_highlight to add their information.
A user-defined exception class can also define their own detailed_message
method to add supplemental information. When highlight
is true, it can return a string containing escape sequences, but use widely-supported ones. It is recommended to limit the following codes:
Reset (\e[0m
)
Bold (\e[1m
)
Underline (\e[4m
)
Foreground color except white and black
Red (\e[31m
)
Green (\e[32m
)
Yellow (\e[33m
)
Blue (\e[34m
)
Magenta (\e[35m
)
Cyan (\e[36m
)
Use escape sequences carefully even if highlight
is true. Do not use escape sequences to express essential information; the message should be readable even if all escape sequences are ignored.
Returns any backtrace associated with the exception. This method is similar to Exception#backtrace
, but the backtrace is an array of Thread::Backtrace::Location
.
This method is not affected by Exception#set_backtrace()
.
Return true if the caused method was called as private.
When this module is included in another, Ruby calls append_features
in this module, passing it the receiving module in mod. Ruby’s default implementation is to add the constants, methods, and module variables of this module to mod if this module has not already been added to mod or one of its ancestors. See also Module#include
.
When this module is prepended in another, Ruby calls prepend_features
in this module, passing it the receiving module in mod. Ruby’s default implementation is to overlay the constants, methods, and module variables of this module to mod if this module has not already been added to mod or one of its ancestors. See also Module#prepend
.
Creates instance variables and corresponding methods that return the value of each instance variable. Equivalent to calling “attr
:name” on each name in turn. String
arguments are converted to symbols. Returns an array of defined method names as symbols.
Creates an accessor method to allow assignment to the attribute symbol.id2name
. String
arguments are converted to symbols. Returns an array of defined method names as symbols.
Defines a named attribute for this module, where the name is symbol.id2name
, creating an instance variable (@name
) and a corresponding access method to read it. Also creates a method called name=
to set the attribute. String
arguments are converted to symbols. Returns an array of defined method names as symbols.
module Mod attr_accessor(:one, :two) #=> [:one, :one=, :two, :two=] end Mod.instance_methods.sort #=> [:one, :one=, :two, :two=]
Returns an array containing the names of the public and protected instance methods in the receiver. For a module, these are the public and protected methods; for a class, they are the instance (not singleton) methods. If the optional parameter is false
, the methods of any ancestors are not included.
module A def method1() end end class B include A def method2() end end class C < B def method3() end end A.instance_methods(false) #=> [:method1] B.instance_methods(false) #=> [:method2] B.instance_methods(true).include?(:method1) #=> true C.instance_methods(false) #=> [:method3] C.instance_methods.include?(:method2) #=> true
Note that method visibility changes in the current class, as well as aliases, are considered as methods of the current class by this method:
class C < B alias method4 method2 protected :method2 end C.instance_methods(false).sort #=> [:method2, :method3, :method4]
Makes a list of existing constants public.
Returns an UnboundMethod
representing the given instance method in mod.
class Interpreter def do_a() print "there, "; end def do_d() print "Hello "; end def do_e() print "!\n"; end def do_v() print "Dave"; end Dispatcher = { "a" => instance_method(:do_a), "d" => instance_method(:do_d), "e" => instance_method(:do_e), "v" => instance_method(:do_v) } def interpret(string) string.each_char {|b| Dispatcher[b].bind(self).call } end end interpreter = Interpreter.new interpreter.interpret('dave')
produces:
Hello there, Dave!