Prepend—Prepend the given strings to str.
a = "!" a.prepend("hello ", "world") #=> "hello world!" a #=> "hello world!"
See also String#concat.
Returns the modulo after division of float by other.
6543.21.modulo(137) #=> 104.21000000000004 6543.21.modulo(137.24) #=> 92.92999999999961
Returns true if float is greater than 0.
Returns true if float is less than 0.
Resumes the fiber from the point at which the last Fiber.yield was called, or starts running it if it is the first call to resume. Arguments passed to resume will be the value of the Fiber.yield expression or will be passed as block parameters to the fiber’s block if this is the first resume.
Alternatively, when resume is called it evaluates to the arguments passed to the next Fiber.yield statement inside the fiber’s block or to the block value if it runs to completion without any Fiber.yield
Returns true if the fiber can still be resumed (or transferred to). After finishing execution of the fiber block this method will always return false. You need to require 'fiber' before using this method.
Returns the current fiber. You need to require 'fiber' before using this method. If you are not running in the context of a fiber this method will return the root fiber.
Calls the block once for each entry in the named directory, passing the filename of each entry as a parameter to the block.
If no block is given, an enumerator is returned instead.
Dir.foreach("testdir") {|x| puts "Got #{x}" }
produces:
Got . Got .. Got config.h Got main.rb
Returns an array containing all of the filenames except for “.” and “..” in the given directory. Will raise a SystemCallError if the named directory doesn’t exist.
The optional encoding keyword argument specifies the encoding of the directory. If not specified, the filesystem encoding is used.
Dir.children("testdir") #=> ["config.h", "main.rb"]
Reads the next entry from dir and returns it as a string. Returns nil at the end of the stream.
d = Dir.new("testdir") d.read #=> "." d.read #=> ".." d.read #=> "config.h"
Returns an array containing all of the filenames except for “.” and “..” in this directory.
d = Dir.new("testdir") d.children #=> ["config.h", "main.rb"]
Repositions dir to the first entry.
d = Dir.new("testdir") d.read #=> "." d.rewind #=> #<Dir:0x401b3fb0> d.read #=> "."
Returns true if the named file is an empty directory, false if it is not a directory or non-empty.
Changes permission bits on the named file(s) to the bit pattern represented by mode_int. Actual effects are operating system dependent (see the beginning of this section). On Unix systems, see chmod(2) for details. Returns the number of files processed.
File.chmod(0644, "testfile", "out") #=> 2
Equivalent to File::chmod, but does not follow symbolic links (so it will change the permissions associated with the link, not the file referenced by the link). Often not available.
Returns the name of the file referenced by the given link. Not available on all platforms.
File.symlink("testfile", "link2test") #=> 0 File.readlink("link2test") #=> "testfile"
Renames the given file to the new name. Raises a SystemCallError if the file cannot be renamed.
File.rename("afile", "afile.bak") #=> 0
Returns the real (absolute) pathname of pathname in the actual filesystem not containing symlinks or useless dots.
If dir_string is given, it is used as a base directory for interpreting relative pathname instead of the current directory.
All components of the pathname must exist when this method is called.
Returns the real (absolute) pathname of pathname in the actual filesystem. The real pathname doesn’t contain symlinks or useless dots.
If dir_string is given, it is used as a base directory for interpreting relative pathname instead of the current directory.
The last component of the real pathname can be nonexistent.
Changes permission bits on file to the bit pattern represented by mode_int. Actual effects are platform dependent; on Unix systems, see chmod(2) for details. Follows symbolic links. Also see File#lchmod.
f = File.new("out", "w"); f.chmod(0644) #=> 0
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 the named file is readable by the effective user and group id of this process. See eaccess(3).
Note that some OS-level security features may cause this to return true even though the file is not readable by the effective user/group.
Returns true if the named file exists and has a zero size.
file_name can be an IO object.