End of Life Ruby 3.1 has reached end of life and gets no more fixes. Switch to Ruby 4.0 →

instance method · added in Ruby 3.1

MatchData#match

mtch.match(n) → string or nil

static VALUE
match_nth(VALUE match, VALUE n)
{
    int i = match_backref_number(match, n);
    struct re_registers *regs = RMATCH_REGS(match);

    backref_number_check(regs, i);

    long start = BEG(i), end = END(i);
    if (start < 0)
        return Qnil;

    return rb_str_subseq(RMATCH(match)->str, start, end - start);
}

Returns the captured substring corresponding to the argument. n can be a string or symbol to reference a named capture.

Example

m = /(.)(.)(\d+)(\d)(\w)?/.match("THX1138.")
m.match(0)       #=> "HX1138"
m.match(4)       #=> "8"
m.match(5)       #=> nil

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

Ruby version changes

3.1
- MatchData#match is added [Feature #18172]

See also #length #match_length #inspect #named_captures also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2

‹ prev#length next ›#match_length