Replaces the contents of self
with the contents of other_string
:
s = 'foo' # => "foo" s.replace('bar') # => "bar"
Returns the result of interpreting leading characters in self
as an integer in the given base
(which must be in (2..36)):
'123456'.to_i # => 123456 '123def'.to_i(16) # => 1195503
Characters past a leading valid number (in the given base
) are ignored:
'12.345'.to_i # => 12 '12345'.to_i(2) # => 1
Returns zero if there is no leading valid number:
'abcdef'.to_i # => 0 '2'.to_i(2) # => 0
Returns the result of interpreting leading characters in self
as a Float:
'3.14159'.to_f # => 3.14159 '1.234e-2'.to_f # => 0.01234
Characters past a leading valid number (in the given base
) are ignored:
'3.14 (pi to two places)'.to_f # => 3.14
Returns zero if there is no leading valid number:
'abcdef'.to_f # => 0.0
Returns self
if self
is a String, or self
converted to a String if self
is a subclass of String.
String#to_str
is an alias for String#to_s
.
Returns a new string with the characters from self
in reverse order.
'stressed'.reverse # => "desserts"
Returns self
with its characters reversed:
s = 'stressed' s.reverse! # => "desserts" s # => "desserts"
Prepends each string in other_strings
to self
and returns self
:
s = 'foo' s.prepend('bar', 'baz') # => "barbazfoo" s # => "barbazfoo"
Related: String#concat
.
If integer is greater than the length of str, returns a new String
of length integer with str left justified and padded with padstr; otherwise, returns str.
"hello".ljust(4) #=> "hello" "hello".ljust(20) #=> "hello " "hello".ljust(20, '1234') #=> "hello123412341234123"
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 the receiver 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 #=> "" "hello".strip #=> "hello"
Returns a copy of the receiver with leading whitespace removed. See also String#rstrip
and String#strip
.
Refer to String#strip
for the definition of whitespace.
" hello ".lstrip #=> "hello " "hello".lstrip #=> "hello"
Returns a copy of the receiver with trailing whitespace removed. See also String#lstrip
and String#strip
.
Refer to String#strip
for the definition of whitespace.
" hello ".rstrip #=> " hello" "hello".rstrip #=> "hello"
Removes leading and trailing whitespace from the receiver. Returns the altered receiver, or nil
if there was no change.
Refer to String#strip
for the definition of whitespace.
" hello ".strip! #=> "hello" "hello".strip! #=> nil
Removes leading whitespace from the receiver. Returns the altered receiver, or nil
if no change was made. See also String#rstrip!
and String#strip!
.
Refer to String#strip
for the definition of whitespace.
" hello ".lstrip! #=> "hello " "hello ".lstrip! #=> nil "hello".lstrip! #=> nil
Removes trailing whitespace from the receiver. Returns the altered receiver, or nil
if no change was made. See also String#lstrip!
and String#strip!
.
Refer to String#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
; depending of the value of self
, the string representation may contain:
A fixed-point number.
A number in “scientific notation” (containing an exponent).
‘Infinity’.
‘-Infinity’.
‘NaN’ (indicating not-a-number).
3.14.to_s # => “3.14” (10.1**50).to_s # => “1.644631821843879e+50” (10.1**500).to_s # => “Infinity” (-10.1**500).to_s # => “-Infinity” (0.0/0.0).to_s # => “NaN”
Returns self
truncated to an Integer
.
1.2.to_i # => 1 (-1.2).to_i # => -1
Note that the limited precision of floating-point arithmetic may lead to surprising results:
(0.3 / 0.1).to_i # => 2 (!)
Float#to_int
is an alias for Float#to_i
.
Returns the largest number less than or equal to self
with a precision of ndigits
decimal digits.
When ndigits
is positive, returns a float with ndigits
digits after the decimal point (as available):
f = 12345.6789 f.floor(1) # => 12345.6 f.floor(3) # => 12345.678 f = -12345.6789 f.floor(1) # => -12345.7 f.floor(3) # => -12345.679
When ndigits
is non-positive, returns an integer with at least ndigits.abs
trailing zeros:
f = 12345.6789 f.floor(0) # => 12345 f.floor(-3) # => 12000 f = -12345.6789 f.floor(0) # => -12346 f.floor(-3) # => -13000
Note that the limited precision of floating-point arithmetic may lead to surprising results:
(0.3 / 0.1).floor #=> 2 (!)
Related: Float#ceil
.
Since float
is already a Float
, returns self
.
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
.
Returns the current fiber. If you are not running in the context of a fiber this method will return the root fiber.
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