class MatchData < Object

MatchData is the type of the special variable $~, and is the type of the object returned by Regexp#match and Regexp#last_match. It encapsulates all the results of a pattern match, results normally accessed through the special variables $&, $', $`, $1, $2, and so on.

instance methods

[ ]

mtch[i] → anObject

mtch[start, length] → anArray

mtch[aRange] → anArray

Match Reference—MatchData acts as an array, and may be accessed using the normal array indexing techniques. mtch[0] is equivalent to the special variable $&, and returns the entire matched string. mtch[1], mtch[2], and so on return the values of the matched backreferences (portions of the pattern between parentheses).

m = /(.)(.)(\d+)(\d)/.match("THX1138.") m[0] → "HX1138" m[1, 2] → ["H", "X"] m[1..3] → ["H", "X", "113"] m[-3, 2] → ["X", "113"]

begin

mtch.begin( n ) → anInteger

Returns the offset of the start of the nth element of the match array in the string.

m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.begin(0) → 1 m.begin(2) → 2

end

mtch.end( n ) → anInteger

Returns the offset of the character immediately following the end of the nth element of the match array in the string.

m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.end(0) → 7 m.end(2) → 3

length

mtch.length → anInteger

Returns the number of elements in the match array.

m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.length → 5 m.size → 5

offset

mtch.offset( n ) → anArray

Returns a two-element array containing the beginning and ending offsets of the nth match.

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

post_match

mtch.post_match → aString

Returns the portion of the original string after the current match. Equivalent to the special variable $'.

m = /(.)(.)(\d+)(\d)/.match("THX1138: The Movie") m.post_match → ": The Movie"

pre_match

mtch.pre_match → aString

Returns the portion of the original string before the current match. Equivalent to the special variable $`.

m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.pre_match → "T"

size

mtch.size → anInteger

A synonym for MatchData#length.

string

mtch.string → aString

Returns a frozen copy of the string passed in to match.

m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.string → "THX1138."

to_a

mtch.to_a → anArray

Returns the array of matches.

m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.to_a → ["HX1138", "H", "X", "113", "8"]

to_s

mtch.to_s → aString

Returns the entire matched string.

m = /(.)(.)(\d+)(\d)/.match("THX1138.") m.to_s → "HX1138"