Method: Regexp.last_match

Defined in:
re.c

.last_match ⇒ MatchData? .last_match(n) ⇒ String? .last_match(name) ⇒ String?

With no argument, returns the value of $~, which is the result of the most recent pattern match (see Regexp global variables):

/c(.)t/ =~ 'cat'  # => 0
Regexp.last_match # => #<MatchData "cat" 1:"a">
/a/ =~ 'foo'      # => nil
Regexp.last_match # => nil

With non-negative integer argument n, returns the _n_th field in the matchdata, if any, or nil if none:

/c(.)t/ =~ 'cat'     # => 0
Regexp.last_match(0) # => "cat"
Regexp.last_match(1) # => "a"
Regexp.last_match(2) # => nil

With negative integer argument n, counts backwards from the last field:

Regexp.last_match(-1)       # => "a"

With string or symbol argument name, returns the string value for the named capture, if any:

/(?<lhs>\w+)\s*=\s*(?<rhs>\w+)/ =~ 'var = val'
Regexp.last_match        # => #<MatchData "var = val" lhs:"var"rhs:"val">
Regexp.last_match(:lhs)  # => "var"
Regexp.last_match('rhs') # => "val"
Regexp.last_match('foo') # Raises IndexError.

Overloads:



4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
 
# File 're.c', line 4642

static VALUE
rb_reg_s_last_match(int argc, VALUE *argv, VALUE _)
{
    if (rb_check_arity(argc, 0, 1) == 1) {
        VALUE match = rb_backref_get();
        int n;
        if (NIL_P(match)) return Qnil;
        n = match_backref_number(match, argv[0]);
        return rb_reg_nth_match(n, match);
    }
    return match_getter();
}