Reads a line from the stream which is separated by eol.
Raises EOFError
if at end of file.
Formats and writes to the stream converting parameters under control of the format string.
See Kernel#sprintf
for format string details.
Create a new repository for the given string.
Check if gem name
version version
is installed.
A Zlib::Inflate#inflate
wrapper
Create parser string nodes from a single prism node. The parser gem “glues” strings together when a line continuation is encountered.
Replaces the elements of self
with the elements of other_array
, which must be an array-convertible object; returns self
:
a = ['a', 'b', 'c'] # => ["a", "b", "c"] a.replace(['d', 'e']) # => ["d", "e"]
Related: see Methods for Assigning.
With a block given, iterates over the elements of self
, passing each array index to the block; returns self
:
a = [:foo, 'bar', 2] a.each_index {|index| puts "#{index} #{a[index]}" }
Output:
0 foo 1 bar 2 2
Allows the array to be modified during iteration:
a = [:foo, 'bar', 2] a.each_index {|index| puts index; a.clear if index > 0 } a # => []
Output:
0 1
With no block given, returns a new Enumerator
.
Related: see Methods for Iterating.
With a block given, calls the block with each repeated combination of length size
of the elements of self
; each combination is an array; returns self
. The order of the combinations is indeterminate.
If a positive integer argument size
is given, calls the block with each size
-tuple repeated combination of the elements of self
. The number of combinations is (size+1)(size+2)/2
.
Examples:
size
is 1:
c = [] [0, 1, 2].repeated_combination(1) {|combination| c.push(combination) } c # => [[0], [1], [2]]
size
is 2:
c = [] [0, 1, 2].repeated_combination(2) {|combination| c.push(combination) } c # => [[0, 0], [0, 1], [0, 2], [1, 1], [1, 2], [2, 2]]
If size
is zero, calls the block once with an empty array.
If size
is negative, does not call the block:
[0, 1, 2].repeated_combination(-1) {|combination| fail 'Cannot happen' }
With no block given, returns a new Enumerator
.
Related: see Methods for Combining.
Returns the integer index of the element from self
found by a binary search, or nil
if the search found no suitable element.
See Binary Searching.
Related: see Methods for Fetching.
Returns self
(which is already an Integer).
Returns self
as an integer; converts using method to_i
in the derived class.
Of the Core and Standard Library classes, only Rational
and Complex
use this implementation.
Examples:
Rational(1, 2).to_int # => 0 Rational(2, 1).to_int # => 2 Complex(2, 0).to_int # => 2 Complex(2, 1).to_int # Raises RangeError (non-zero imaginary part)
Replaces the contents of self
with the contents of other_string
:
s = 'foo' # => "foo" s.replace('bar') # => "bar"
With a block given, forms the substrings (“lines”) that are the result of splitting self
at each occurrence of the given line separator line_sep
; passes each line to the block; returns self
:
s = <<~EOT This is the first line. This is line two. This is line four. This is line five. EOT s.each_line {|line| p line }
Output:
"This is the first line.\n" "This is line two.\n" "\n" "This is line four.\n" "This is line five.\n"
With a different line_sep
:
s.each_line(' is ') {|line| p line }
Output:
"This is " "the first line.\nThis is " "line two.\n\nThis is " "line four.\nThis is " "line five.\n"
With chomp
as true
, removes the trailing line_sep
from each line:
s.each_line(chomp: true) {|line| p line }
Output:
"This is the first line." "This is line two." "" "This is line four." "This is line five."
With an empty string as line_sep
, forms and passes “paragraphs” by splitting at each occurrence of two or more newlines:
s.each_line('') {|line| p line }
Output:
"This is the first line.\nThis is line two.\n\n" "This is line four.\nThis is line five.\n"
With no block given, returns an enumerator.
Calls the given block with each successive codepoint from self
; each codepoint is the integer value for a character; returns self
:
'hello'.each_codepoint {|codepoint| print codepoint, ' ' } print "\n" 'тест'.each_codepoint {|codepoint| print codepoint, ' ' } print "\n" 'こんにちは'.each_codepoint {|codepoint| print codepoint, ' ' } print "\n"
Output:
104 101 108 108 111 1090 1077 1089 1090 12371 12435 12395 12385 12399
Returns an enumerator if no block is given.
Changes the encoding of self
to encoding
, which may be a string encoding name or an Encoding
object; returns self:
s = 'łał' s.bytes # => [197, 130, 97, 197, 130] s.encoding # => #<Encoding:UTF-8> s.force_encoding('ascii') # => "\xC5\x82a\xC5\x82" s.encoding # => #<Encoding:US-ASCII>
Does not change the underlying bytes:
s.bytes # => [197, 130, 97, 197, 130]
Makes the change even if the given encoding
is invalid for self
(as is the change above):
s.valid_encoding? # => false s.force_encoding(Encoding::UTF_8) # => "łał" s.valid_encoding? # => true
Returns true
if self
is encoded correctly, false
otherwise:
"\xc2\xa1".force_encoding(Encoding::UTF_8).valid_encoding? # => true "\xc2".force_encoding(Encoding::UTF_8).valid_encoding? # => false "\x80".force_encoding(Encoding::UTF_8).valid_encoding? # => false