If integer is greater than the length of str, returns a new String of length integer with str right justified and padded with padstr; otherwise, returns str.
"hello".rjust(4) #=> "hello" "hello".rjust(20) #=> " hello" "hello".rjust(20, '1234') #=> "123412341234123hello"
Returns a copy of str with leading and trailing whitespace removed.
Whitespace is defined as any of the following characters: null, horizontal tab, line feed, vertical tab, form feed, carriage return, space.
" hello ".strip #=> "hello" "\tgoodbye\r\n".strip #=> "goodbye" "\x00\t\n\v\f\r ".strip #=> ""
Returns a copy of str with leading whitespace removed. See also String#rstrip and String#strip.
Refer to strip for the definition of whitespace.
" hello ".lstrip #=> "hello " "hello".lstrip #=> "hello"
Returns a copy of str with trailing whitespace removed. See also String#lstrip and String#strip.
Refer to strip for the definition of whitespace.
" hello ".rstrip #=> " hello" "hello".rstrip #=> "hello"
Removes leading and trailing whitespace from str. Returns nil if str was not altered.
Refer to strip for the definition of whitespace.
Removes leading whitespace from str, returning nil if no change was made. See also String#rstrip! and String#strip!.
Refer to strip for the definition of whitespace.
" hello ".lstrip! #=> "hello " "hello ".lstrip! #=> nil "hello".lstrip! #=> nil
Removes trailing whitespace from str, returning nil if no change was made. See also String#lstrip! and String#strip!.
Refer to strip for the definition of whitespace.
" hello ".rstrip! #=> " hello" " hello".rstrip! #=> nil "hello".rstrip! #=> nil
Returns the value of float as a BigDecimal. The precision parameter is used to determine the number of significant digits for the result (the default is Float::DIG).
require 'bigdecimal' require 'bigdecimal/util' 0.5.to_d # => 0.5e0 1.234.to_d(2) # => 0.12e1
See also BigDecimal::new.
Returns a string containing a representation of self. As well as a fixed or exponential form of the float, the call may return NaN, Infinity, and -Infinity.
Since float is already a Float, returns self.
Returns the float truncated to an Integer.
1.2.to_i #=> 1 (-1.2).to_i #=> -1
Note that the limited precision of floating point arithmetic might lead to surprising results:
(0.3 / 0.1).to_i #=> 2 (!)
Returns the largest number less than or equal to float with a precision of ndigits decimal digits (default: 0).
When the precision is negative, the returned value is an integer with at least ndigits.abs trailing zeros.
Returns a floating point number when ndigits is positive, otherwise returns an integer.
1.2.floor #=> 1 2.0.floor #=> 2 (-1.2).floor #=> -2 (-2.0).floor #=> -2 1.234567.floor(2) #=> 1.23 1.234567.floor(3) #=> 1.234 1.234567.floor(4) #=> 1.2345 1.234567.floor(5) #=> 1.23456 34567.89.floor(-5) #=> 0 34567.89.floor(-4) #=> 30000 34567.89.floor(-3) #=> 34000 34567.89.floor(-2) #=> 34500 34567.89.floor(-1) #=> 34560 34567.89.floor(0) #=> 34567 34567.89.floor(1) #=> 34567.8 34567.89.floor(2) #=> 34567.89 34567.89.floor(3) #=> 34567.89
Note that the limited precision of floating point arithmetic might lead to surprising results:
(0.3 / 0.1).floor #=> 2 (!)
Returns the value as a rational.
2.0.to_r #=> (2/1) 2.5.to_r #=> (5/2) -0.75.to_r #=> (-3/4) 0.0.to_r #=> (0/1) 0.3.to_r #=> (5404319552844595/18014398509481984)
NOTE: 0.3.to_r isn’t the same as “0.3”.to_r. The latter is equivalent to “3/10”.to_r, but the former isn’t so.
0.3.to_r == 3/10r #=> false "0.3".to_r == 3/10r #=> true
See also Float#rationalize.
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 fiber information string.
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.
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"
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 a directory, false otherwise.
Deprecated method. Don’t use.
Returns a File::Stat object for the named file (see File::Stat).
File.stat("testfile").mtime #=> Tue Apr 08 12:58:04 CDT 2003
Same as File::stat, but does not follow the last symbolic link. Instead, reports on the link itself.
File.symlink("testfile", "link2test") #=> 0 File.stat("testfile").size #=> 66 File.lstat("link2test").size #=> 8 File.stat("link2test").size #=> 66
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