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instance method

MatchData#offset

(::MatchData::capture backref) -> ([ ::Integer, ::Integer ] | [ nil, nil ])
offset(n) → [start_offset, end_offset]
offset(name) → [start_offset, end_offset]

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:

Example
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:

Example
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.

See also #names #post_match #named_captures #pre_match also in 4.1 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0