| RelativeLocationPath | '/' RelativeLocationPath? | '//' RelativeLocationPath
Set Union — Returns a new array by joining other_arys with self, excluding any duplicates and preserving the order from the given arrays.
It compares elements using their hash and eql? methods for efficiency.
[ "a", "b", "c" ].union( [ "c", "d", "a" ] ) #=> [ "a", "b", "c", "d" ] [ "a" ].union( ["e", "b"], ["a", "c", "b"] ) #=> [ "a", "e", "b", "c" ] [ "a" ].union #=> [ "a" ]
See also Array#|.
Inserts the given values before the element with the given index.
Negative indices count backwards from the end of the array, where -1 is the last element. If a negative index is used, the given values will be inserted after that element, so using an index of -1 will insert the values at the end of the array.
a = %w{ a b c d } a.insert(2, 99) #=> ["a", "b", 99, "c", "d"] a.insert(-2, 1, 2, 3) #=> ["a", "b", 99, "c", 1, 2, 3, "d"]
By using binary search, finds a value from this array which meets the given condition in O(log n) where n is the size of the array.
You can use this method in two modes: a find-minimum mode and a find-any mode. In either case, the elements of the array must be monotone (or sorted) with respect to the block.
In find-minimum mode (this is a good choice for typical use cases), the block must always return true or false, and there must be an index i (0 <= i <= ary.size) so that:
the block returns false for any element whose index is less than i, and
the block returns true for any element whose index is greater than or equal to i.
This method returns the i-th element. If i is equal to ary.size, it returns nil.
ary = [0, 4, 7, 10, 12] ary.bsearch {|x| x >= 4 } #=> 4 ary.bsearch {|x| x >= 6 } #=> 7 ary.bsearch {|x| x >= -1 } #=> 0 ary.bsearch {|x| x >= 100 } #=> nil
In find-any mode (this behaves like libc’s bsearch(3)), the block must always return a number, and there must be two indices i and j (0 <= i <= j <= ary.size) so that:
the block returns a positive number for ary if 0 <= k < i,
the block returns zero for ary if i <= k < j, and
the block returns a negative number for ary if j <= k < ary.size.
Under this condition, this method returns any element whose index is within i…j. If i is equal to j (i.e., there is no element that satisfies the block), this method returns nil.
ary = [0, 4, 7, 10, 12] # try to find v such that 4 <= v < 8 ary.bsearch {|x| 1 - x / 4 } #=> 4 or 7 # try to find v such that 8 <= v < 10 ary.bsearch {|x| 4 - x / 2 } #=> nil
You must not mix the two modes at a time; the block must always return either true/false, or always return a number. It is undefined which value is actually picked up at each iteration.
Returns self if num is not zero, nil otherwise.
This behavior is useful when chaining comparisons:
a = %w( z Bb bB bb BB a aA Aa AA A ) b = a.sort {|a,b| (a.downcase <=> b.downcase).nonzero? || a <=> b } b #=> ["A", "a", "AA", "Aa", "aA", "BB", "Bb", "bB", "bb", "z"]
Decodes str (which may contain binary data) according to the format string, returning an array of each value extracted. The format string consists of a sequence of single-character directives, summarized in the table at the end of this entry. Each directive may be followed by a number, indicating the number of times to repeat with this directive. An asterisk (“*”) will use up all remaining elements. The directives sSiIlL may each be followed by an underscore (“_”) or exclamation mark (“!”) to use the underlying platform’s native size for the specified type; otherwise, it uses a platform-independent consistent size. Spaces are ignored in the format string. See also String#unpack1, Array#pack.
"abc \0\0abc \0\0".unpack('A6Z6') #=> ["abc", "abc "] "abc \0\0".unpack('a3a3') #=> ["abc", " \000\000"] "abc \0abc \0".unpack('Z*Z*') #=> ["abc ", "abc "] "aa".unpack('b8B8') #=> ["10000110", "01100001"] "aaa".unpack('h2H2c') #=> ["16", "61", 97] "\xfe\xff\xfe\xff".unpack('sS') #=> [-2, 65534] "now=20is".unpack('M*') #=> ["now is"] "whole".unpack('xax2aX2aX1aX2a') #=> ["h", "e", "l", "l", "o"]
This table summarizes the various formats and the Ruby classes returned by each.
Integer | |
Directive | Returns | Meaning
------------------------------------------------------------------
C | Integer | 8-bit unsigned (unsigned char)
S | Integer | 16-bit unsigned, native endian (uint16_t)
L | Integer | 32-bit unsigned, native endian (uint32_t)
Q | Integer | 64-bit unsigned, native endian (uint64_t)
J | Integer | pointer width unsigned, native endian (uintptr_t)
| |
c | Integer | 8-bit signed (signed char)
s | Integer | 16-bit signed, native endian (int16_t)
l | Integer | 32-bit signed, native endian (int32_t)
q | Integer | 64-bit signed, native endian (int64_t)
j | Integer | pointer width signed, native endian (intptr_t)
| |
S_ S! | Integer | unsigned short, native endian
I I_ I! | Integer | unsigned int, native endian
L_ L! | Integer | unsigned long, native endian
Q_ Q! | Integer | unsigned long long, native endian (ArgumentError
| | if the platform has no long long type.)
J! | Integer | uintptr_t, native endian (same with J)
| |
s_ s! | Integer | signed short, native endian
i i_ i! | Integer | signed int, native endian
l_ l! | Integer | signed long, native endian
q_ q! | Integer | signed long long, native endian (ArgumentError
| | if the platform has no long long type.)
j! | Integer | intptr_t, native endian (same with j)
| |
S> s> S!> s!> | Integer | same as the directives without ">" except
L> l> L!> l!> | | big endian
I!> i!> | |
Q> q> Q!> q!> | | "S>" is same as "n"
J> j> J!> j!> | | "L>" is same as "N"
| |
S< s< S!< s!< | Integer | same as the directives without "<" except
L< l< L!< l!< | | little endian
I!< i!< | |
Q< q< Q!< q!< | | "S<" is same as "v"
J< j< J!< j!< | | "L<" is same as "V"
| |
n | Integer | 16-bit unsigned, network (big-endian) byte order
N | Integer | 32-bit unsigned, network (big-endian) byte order
v | Integer | 16-bit unsigned, VAX (little-endian) byte order
V | Integer | 32-bit unsigned, VAX (little-endian) byte order
| |
U | Integer | UTF-8 character
w | Integer | BER-compressed integer (see Array.pack)
Float | |
Directive | Returns | Meaning
-----------------------------------------------------------------
D d | Float | double-precision, native format
F f | Float | single-precision, native format
E | Float | double-precision, little-endian byte order
e | Float | single-precision, little-endian byte order
G | Float | double-precision, network (big-endian) byte order
g | Float | single-precision, network (big-endian) byte order
String | |
Directive | Returns | Meaning
-----------------------------------------------------------------
A | String | arbitrary binary string (remove trailing nulls and ASCII spaces)
a | String | arbitrary binary string
Z | String | null-terminated string
B | String | bit string (MSB first)
b | String | bit string (LSB first)
H | String | hex string (high nibble first)
h | String | hex string (low nibble first)
u | String | UU-encoded string
M | String | quoted-printable, MIME encoding (see RFC2045)
m | String | base64 encoded string (RFC 2045) (default)
| | base64 encoded string (RFC 4648) if followed by 0
P | String | pointer to a structure (fixed-length string)
p | String | pointer to a null-terminated string
Misc. | |
Directive | Returns | Meaning
-----------------------------------------------------------------
@ | --- | skip to the offset given by the length argument
X | --- | skip backward one byte
x | --- | skip forward one byte
HISTORY
J, J! j, and j! are available since Ruby 2.3.
Q_, Q!, q_, and q! are available since Ruby 2.1.
I!<, i!<, I!>, and i!> are available since Ruby 1.9.3.
Decodes str (which may contain binary data) according to the format string, returning the first value extracted. See also String#unpack, Array#pack.
Contrast with String#unpack:
"abc \0\0abc \0\0".unpack('A6Z6') #=> ["abc", "abc "] "abc \0\0abc \0\0".unpack1('A6Z6') #=> "abc"
In that case data would be lost but often it’s the case that the array only holds one value, especially when unpacking binary data. For instance:
“xffx00x00x00”.unpack(“l”) #=> [255] “xffx00x00x00”.unpack1(“l”) #=> 255
Thus unpack1 is convenient, makes clear the intention and signals the expected return value to those reading the code.
Inserts other_str before the character at the given index, modifying str. Negative indices count from the end of the string, and insert after the given character. The intent is insert aString so that it starts at the given index.
"abcd".insert(0, 'X') #=> "Xabcd" "abcd".insert(3, 'X') #=> "abcXd" "abcd".insert(4, 'X') #=> "abcdX" "abcd".insert(-3, 'X') #=> "abXcd" "abcd".insert(-1, 'X') #=> "abcdX"
Returns an array of characters in str. This is a shorthand for str.each_char.to_a.
If a block is given, which is a deprecated form, works the same as each_char.
Checks the compatibility of two objects.
If the objects are both strings they are compatible when they are concatenatable. The encoding of the concatenated string will be returned if they are compatible, nil if they are not.
Encoding.compatible?("\xa1".force_encoding("iso-8859-1"), "b") #=> #<Encoding:ISO-8859-1> Encoding.compatible?( "\xa1".force_encoding("iso-8859-1"), "\xa1\xa1".force_encoding("euc-jp")) #=> nil
If the objects are non-strings their encodings are compatible when they have an encoding and:
Either encoding is US-ASCII compatible
One of the encodings is a 7-bit encoding
Returns self if the value is non-zero, nil otherwise.
Parses the given representation of date and time with the given template, and returns a hash of parsed elements. _strptime does not support specification of flags and width unlike strftime.
Date._strptime('2001-02-03', '%Y-%m-%d') #=> {:year=>2001, :mon=>2, :mday=>3}
See also strptime(3) and strftime.
Parses the given representation of date and time with the given template, and creates a date object. strptime does not support specification of flags and width unlike strftime.
Date.strptime('2001-02-03', '%Y-%m-%d') #=> #<Date: 2001-02-03 ...> Date.strptime('03-02-2001', '%d-%m-%Y') #=> #<Date: 2001-02-03 ...> Date.strptime('2001-034', '%Y-%j') #=> #<Date: 2001-02-03 ...> Date.strptime('2001-W05-6', '%G-W%V-%u') #=> #<Date: 2001-02-03 ...> Date.strptime('2001 04 6', '%Y %U %w') #=> #<Date: 2001-02-03 ...> Date.strptime('2001 05 6', '%Y %W %u') #=> #<Date: 2001-02-03 ...> Date.strptime('sat3feb01', '%a%d%b%y') #=> #<Date: 2001-02-03 ...>
See also strptime(3) and strftime.
Parses the given representation of date and time with the given template, and returns a hash of parsed elements. _strptime does not support specification of flags and width unlike strftime.
See also strptime(3) and strftime.
Parses the given representation of date and time with the given template, and creates a DateTime object. strptime does not support specification of flags and width unlike strftime.
DateTime.strptime('2001-02-03T04:05:06+07:00', '%Y-%m-%dT%H:%M:%S%z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('03-02-2001 04:05:06 PM', '%d-%m-%Y %I:%M:%S %p') #=> #<DateTime: 2001-02-03T16:05:06+00:00 ...> DateTime.strptime('2001-W05-6T04:05:06+07:00', '%G-W%V-%uT%H:%M:%S%z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('2001 04 6 04 05 06 +7', '%Y %U %w %H %M %S %z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('2001 05 6 04 05 06 +7', '%Y %W %u %H %M %S %z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('-1', '%s') #=> #<DateTime: 1969-12-31T23:59:59+00:00 ...> DateTime.strptime('-1000', '%Q') #=> #<DateTime: 1969-12-31T23:59:59+00:00 ...> DateTime.strptime('sat3feb014pm+7', '%a%d%b%y%H%p%z') #=> #<DateTime: 2001-02-03T16:00:00+07:00 ...>
See also strptime(3) and strftime.
Works similar to parse except that instead of using a heuristic to detect the format of the input string, you provide a second argument that describes the format of the string.
If a block is given, the year described in date is converted by the block. For example:
Time.strptime(...) {|y| y < 100 ? (y >= 69 ? y + 1900 : y + 2000) : y}
Below is a list of the formatting options:
The abbreviated weekday name (“Sun”)
The full weekday name (“Sunday”)
The abbreviated month name (“Jan”)
The full month name (“January”)
The preferred local date and time representation
Century (20 in 2009)
Day of the month (01..31)
Date (%m/%d/%y)
Day of the month, blank-padded ( 1..31)
Equivalent to %Y-%m-%d (the ISO 8601 date format)
The last two digits of the commercial year
The week-based year according to ISO-8601 (week 1 starts on Monday and includes January 4)
Equivalent to %b
Hour of the day, 24-hour clock (00..23)
Hour of the day, 12-hour clock (01..12)
Day of the year (001..366)
hour, 24-hour clock, blank-padded ( 0..23)
hour, 12-hour clock, blank-padded ( 0..12)
Millisecond of the second (000..999)
Month of the year (01..12)
Minute of the hour (00..59)
Newline (n)
Fractional seconds digits
Meridian indicator (“AM” or “PM”)
Meridian indicator (“am” or “pm”)
time, 12-hour (same as %I:%M:%S %p)
time, 24-hour (%H:%M)
Number of seconds since 1970-01-01 00:00:00 UTC.
Second of the minute (00..60)
Tab character (t)
time, 24-hour (%H:%M:%S)
Day of the week as a decimal, Monday being 1. (1..7)
Week number of the current year, starting with the first Sunday as the first day of the first week (00..53)
VMS date (%e-%b-%Y)
Week number of year according to ISO 8601 (01..53)
Week number of the current year, starting with the first Monday as the first day of the first week (00..53)
Day of the week (Sunday is 0, 0..6)
Preferred representation for the date alone, no time
Preferred representation for the time alone, no date
Year without a century (00..99)
Year which may include century, if provided
Time zone as hour offset from UTC (e.g. +0900)
Time zone name
Literal “%” character
date(1) (%a %b %e %H:%M:%S %Z %Y)
require 'time' Time.strptime("2000-10-31", "%Y-%m-%d") #=> 2000-10-31 00:00:00 -0500
You must require ‘time’ to use this method.
Returns the struct members as an array of symbols:
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.members #=> [:name, :address, :zip]
Returns pathname configuration variable using fpathconf().
name should be a constant under Etc which begins with PC_.
The return value is an integer or nil. nil means indefinite limit. (fpathconf() returns -1 but errno is not set.)
require 'etc' IO.pipe {|r, w| p w.pathconf(Etc::PC_PIPE_BUF) #=> 4096 }
By using binary search, finds a value in range which meets the given condition in O(log n) where n is the size of the range.
You can use this method in two use cases: a find-minimum mode and a find-any mode. In either case, the elements of the range must be monotone (or sorted) with respect to the block.
In find-minimum mode (this is a good choice for typical use case), the block must return true or false, and there must be a value x so that:
the block returns false for any value which is less than x, and
the block returns true for any value which is greater than or equal to x.
If x is within the range, this method returns the value x. Otherwise, it returns nil.
ary = [0, 4, 7, 10, 12] (0...ary.size).bsearch {|i| ary[i] >= 4 } #=> 1 (0...ary.size).bsearch {|i| ary[i] >= 6 } #=> 2 (0...ary.size).bsearch {|i| ary[i] >= 8 } #=> 3 (0...ary.size).bsearch {|i| ary[i] >= 100 } #=> nil (0.0...Float::INFINITY).bsearch {|x| Math.log(x) >= 0 } #=> 1.0
In find-any mode (this behaves like libc’s bsearch(3)), the block must return a number, and there must be two values x and y (x <= y) so that:
the block returns a positive number for v if v < x,
the block returns zero for v if x <= v < y, and
the block returns a negative number for v if y <= v.
This method returns any value which is within the intersection of the given range and x…y (if any). If there is no value that satisfies the condition, it returns nil.
ary = [0, 100, 100, 100, 200] (0..4).bsearch {|i| 100 - ary[i] } #=> 1, 2 or 3 (0..4).bsearch {|i| 300 - ary[i] } #=> nil (0..4).bsearch {|i| 50 - ary[i] } #=> nil
You must not mix the two modes at a time; the block must always return either true/false, or always return a number. It is undefined which value is actually picked up at each iteration.
Return a Regexp object that is the union of the given patterns, i.e., will match any of its parts. The patterns can be Regexp objects, in which case their options will be preserved, or Strings. If no patterns are given, returns /(?!)/. The behavior is unspecified if any given pattern contains capture.
Regexp.union #=> /(?!)/ Regexp.union("penzance") #=> /penzance/ Regexp.union("a+b*c") #=> /a\+b\*c/ Regexp.union("skiing", "sledding") #=> /skiing|sledding/ Regexp.union(["skiing", "sledding"]) #=> /skiing|sledding/ Regexp.union(/dogs/, /cats/i) #=> /(?-mix:dogs)|(?i-mx:cats)/
Note: the arguments for ::union will try to be converted into a regular expression literal via to_regexp.