class MatchData

Returns true if object is another MatchData object whose target string, regexp, match, and captures are the same as self, false otherwise.

When arguments index, +start and length, or range are given, returns match and captures in the style of Array#[]:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m[0] # => "HX1138"
m[1, 2]  # => ["H", "X"]
m[1..3]  # => ["H", "X", "113"]
m[-3, 2] # => ["X", "113"]

When string or symbol argument name is given, returns the matched substring for the given name:

m = /(?<foo>.)(.)(?<bar>.+)/.match("hoge")
# => #<MatchData "hoge" foo:"h" bar:"ge">
m['foo'] # => "h"
m[:bar]  # => "ge"

If multiple captures have the same name, returns the last matched substring.

m = /(?<foo>.)(?<foo>.+)/.match("hoge")
# => #<MatchData "hoge" foo:"h" foo:"oge">
m[:foo] #=> "oge"

m = /\W(?<foo>.+)|\w(?<foo>.+)|(?<foo>.+)/.match("hoge")
#<MatchData "hoge" foo:nil foo:"oge" foo:nil>
m[:foo] #=> "oge"

Returns the offset (in characters) of the beginning of the specified match.

When non-negative integer argument n is given, returns the offset of the beginning of the nth match:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m[0]       # => "HX1138"
m.begin(0) # => 1
m[3]       # => "113"
m.begin(3) # => 3

m = /(т)(е)(с)/.match('тест')
# => #<MatchData "тес" 1:"т" 2:"е" 3:"с">
m[0]       # => "тес"
m.begin(0) # => 0
m[3]       # => "с"
m.begin(3) # => 2

When string or symbol argument name is given, returns the offset of the beginning for the named match:

m = /(?<foo>.)(.)(?<bar>.)/.match("hoge")
# => #<MatchData "hog" foo:"h" bar:"g">
m[:foo]        # => "h"
m.begin('foo') # => 0
m[:bar]        # => "g"
m.begin(:bar)  # => 2

Related: MatchData#end, MatchData#offset, MatchData#byteoffset.

Returns the offset (in bytes) of the beginning of the specified match.

When non-negative integer argument n is given, returns the offset of the beginning of the nth match:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m[0]       # => "HX1138"
m.bytebegin(0) # => 1
m[3]       # => "113"
m.bytebegin(3) # => 3

m = /(т)(е)(с)/.match('тест')
# => #<MatchData "тес" 1:"т" 2:"е" 3:"с">
m[0]       # => "тес"
m.bytebegin(0) # => 0
m[3]       # => "с"
m.bytebegin(3) # => 4

When string or symbol argument name is given, returns the offset of the beginning for the named match:

m = /(?<foo>.)(.)(?<bar>.)/.match("hoge")
# => #<MatchData "hog" foo:"h" bar:"g">
m[:foo]        # => "h"
m.bytebegin('foo') # => 0
m[:bar]        # => "g"
m.bytebegin(:bar)  # => 2

Related: MatchData#byteend, MatchData#byteoffset.

Returns the offset (in bytes) of the end of the specified match.

When non-negative integer argument n is given, returns the offset of the end of the nth match:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m[0]     # => "HX1138"
m.byteend(0) # => 7
m[3]     # => "113"
m.byteend(3) # => 6

m = /(т)(е)(с)/.match('тест')
# => #<MatchData "тес" 1:"т" 2:"е" 3:"с">
m[0]     # => "тес"
m.byteend(0) # => 6
m[3]     # => "с"
m.byteend(3) # => 6

When string or symbol argument name is given, returns the offset of the end for the named match:

m = /(?<foo>.)(.)(?<bar>.)/.match("hoge")
# => #<MatchData "hog" foo:"h" bar:"g">
m[:foo]      # => "h"
m.byteend('foo') # => 1
m[:bar]      # => "g"
m.byteend(:bar)  # => 3

Related: MatchData#bytebegin, MatchData#byteoffset.

Returns a two-element array containing the beginning and ending byte-based offsets of the _n_th match. n can be a string or symbol to reference a named capture.

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
m.byteoffset(0)      #=> [1, 7]
m.byteoffset(4)      #=> [6, 7]

m = /(?<foo>.)(.)(?<bar>.)/.match("hoge")
p m.byteoffset(:foo) #=> [0, 1]
p m.byteoffset(:bar) #=> [2, 3]

Returns the array of captures, which are all matches except m[0]:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m[0]       # => "HX1138"
m.captures # => ["H", "X", "113", "8"]

Related: MatchData.to_a.

Returns a hash of the named captures for the given names.

m = /(?<hours>\d{2}):(?<minutes>\d{2}):(?<seconds>\d{2})/.match("18:37:22")
m.deconstruct_keys([:hours, :minutes]) # => {:hours => "18", :minutes => "37"}
m.deconstruct_keys(nil) # => {:hours => "18", :minutes => "37", :seconds => "22"}

Returns an empty hash if no named captures were defined:

m = /(\d{2}):(\d{2}):(\d{2})/.match("18:37:22")
m.deconstruct_keys(nil) # => {}

Returns the offset (in characters) of the end of the specified match.

When non-negative integer argument n is given, returns the offset of the end of the nth match:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m[0]     # => "HX1138"
m.end(0) # => 7
m[3]     # => "113"
m.end(3) # => 6

m = /(т)(е)(с)/.match('тест')
# => #<MatchData "тес" 1:"т" 2:"е" 3:"с">
m[0]     # => "тес"
m.end(0) # => 3
m[3]     # => "с"
m.end(3) # => 3

When string or symbol argument name is given, returns the offset of the end for the named match:

m = /(?<foo>.)(.)(?<bar>.)/.match("hoge")
# => #<MatchData "hog" foo:"h" bar:"g">
m[:foo]      # => "h"
m.end('foo') # => 1
m[:bar]      # => "g"
m.end(:bar)  # => 3

Related: MatchData#begin, MatchData#offset, MatchData#byteoffset.

Returns the integer hash value for self, based on the target string, regexp, match, and captures.

See also Object#hash.

Returns a string representation of self:

m = /.$/.match("foo")
# => #<MatchData "o">
m.inspect # => "#<MatchData \"o\">"

m = /(.)(.)(.)/.match("foo")
# => #<MatchData "foo" 1:"f" 2:"o" 3:"o">
m.inspect # => "#<MatchData \"foo\" 1:\"f\" 2:\"o\

m = /(.)(.)?(.)/.match("fo")
# => #<MatchData "fo" 1:"f" 2:nil 3:"o">
m.inspect # => "#<MatchData \"fo\" 1:\"f\" 2:nil 3:\"o\">"

Related: MatchData#to_s.

Returns the matched substring corresponding to the given argument.

When non-negative argument n is given, returns the matched substring for the nth match:

m = /(.)(.)(\d+)(\d)(\w)?/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8" 5:nil>
m.match(0) # => "HX1138"
m.match(4) # => "8"
m.match(5) # => nil

When string or symbol argument name is given, returns the matched substring for the given name:

m = /(?<foo>.)(.)(?<bar>.+)/.match("hoge")
# => #<MatchData "hoge" foo:"h" bar:"ge">
m.match('foo') # => "h"
m.match(:bar)  # => "ge"

Returns the length (in characters) of the matched substring corresponding to the given argument.

When non-negative argument n is given, returns the length of the matched substring for the nth match:

m = /(.)(.)(\d+)(\d)(\w)?/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8" 5:nil>
m.match_length(0) # => 6
m.match_length(4) # => 1
m.match_length(5) # => nil

When string or symbol argument name is given, returns the length of the matched substring for the named match:

m = /(?<foo>.)(.)(?<bar>.+)/.match("hoge")
# => #<MatchData "hoge" foo:"h" bar:"ge">
m.match_length('foo') # => 1
m.match_length(:bar)  # => 2

Returns a hash of the named captures; each key is a capture name; each value is its captured string or nil:

m = /(?<foo>.)(.)(?<bar>.+)/.match("hoge")
# => #<MatchData "hoge" foo:"h" bar:"ge">
m.named_captures # => {"foo"=>"h", "bar"=>"ge"}

m = /(?<a>.)(?<b>.)/.match("01")
# => #<MatchData "01" a:"0" b:"1">
m.named_captures #=> {"a" => "0", "b" => "1"}

m = /(?<a>.)(?<b>.)?/.match("0")
# => #<MatchData "0" a:"0" b:nil>
m.named_captures #=> {"a" => "0", "b" => nil}

m = /(?<a>.)(?<a>.)/.match("01")
# => #<MatchData "01" a:"0" a:"1">
m.named_captures #=> {"a" => "1"}

If keyword argument symbolize_names is given a true value, the keys in the resulting hash are Symbols:

m = /(?<a>.)(?<a>.)/.match("01")
# => #<MatchData "01" a:"0" a:"1">
m.named_captures(symbolize_names: true) #=> {:a => "1"}

Returns an array of the capture names (see Named Captures):

m = /(?<foo>.)(?<bar>.)(?<baz>.)/.match("hoge")
# => #<MatchData "hog" foo:"h" bar:"o" baz:"g">
m.names # => ["foo", "bar", "baz"]

m = /foo/.match('foo') # => #<MatchData "foo">
m.names # => [] # No named captures.

Equivalent to:

m = /(?<foo>.)(?<bar>.)(?<baz>.)/.match("hoge")
m.regexp.names # => ["foo", "bar", "baz"]

Returns a 2-element array containing the beginning and ending offsets (in characters) of the specified match.

When non-negative integer argument n is given, returns the starting and ending offsets of the nth match:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m[0]        # => "HX1138"
m.offset(0) # => [1, 7]
m[3]        # => "113"
m.offset(3) # => [3, 6]

m = /(т)(е)(с)/.match('тест')
# => #<MatchData "тес" 1:"т" 2:"е" 3:"с">
m[0]        # => "тес"
m.offset(0) # => [0, 3]
m[3]        # => "с"
m.offset(3) # => [2, 3]

When string or symbol argument name is given, returns the starting and ending offsets for the named match:

m = /(?<foo>.)(.)(?<bar>.)/.match("hoge")
# => #<MatchData "hog" foo:"h" bar:"g">
m[:foo]         # => "h"
m.offset('foo') # => [0, 1]
m[:bar]         # => "g"
m.offset(:bar)  # => [2, 3]

Related: MatchData#byteoffset, MatchData#begin, MatchData#end.

Returns the substring of the target string from the end of the first match in self (that is, self[0]) to the end of the string; equivalent to regexp global variable $':

m = /(.)(.)(\d+)(\d)/.match("THX1138: The Movie")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m[0]         # => "HX1138"
m.post_match # => ": The Movie"\

Related: MatchData.pre_match.

Returns the substring of the target string from its beginning up to the first match in self (that is, self[0]); equivalent to regexp global variable $`:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m[0]        # => "HX1138"
m.pre_match # => "T"

Related: MatchData#post_match.

Returns the regexp that produced the match:

m = /a.*b/.match("abc") # => #<MatchData "ab">
m.regexp                # => /a.*b/

Returns size of the match array:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m.size # => 5

Returns the target string if it was frozen; otherwise, returns a frozen copy of the target string:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m.string # => "THX1138."

Returns the array of matches:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m.to_a # => ["HX1138", "H", "X", "113", "8"]

Related: MatchData#captures.

Returns the matched string:

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m.to_s # => "HX1138"

m = /(?<foo>.)(.)(?<bar>.+)/.match("hoge")
# => #<MatchData "hoge" foo:"h" bar:"ge">
m.to_s # => "hoge"

Related: MatchData.inspect.

Returns match and captures at the given indexes, which may include any mixture of:

• Integers.

• Ranges.

• Names (strings and symbols).

Examples:

m = /(.)(.)(\d+)(\d)/.match("THX1138: The Movie")
# => #<MatchData "HX1138" 1:"H" 2:"X" 3:"113" 4:"8">
m.values_at(0, 2, -2) # => ["HX1138", "X", "113"]
m.values_at(1..2, -1) # => ["H", "X", "8"]

m = /(?<a>\d+) *(?<op>[+\-*\/]) *(?<b>\d+)/.match("1 + 2")
# => #<MatchData "1 + 2" a:"1" op:"+" b:"2">
m.values_at(0, 1..2, :a, :b, :op)
# => ["1 + 2", "1", "+", "1", "2", "+"]