Method: MatchData#deconstruct_keys

Defined in:

re.c

#deconstruct_keys(array_of_names) ⇒ Hash

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:

• (Hash)

# File 're.c', line 2477

static VALUE
match_deconstruct_keys(VALUE match, VALUE keys)
{
    VALUE h;
    long i;

    match_check(match);

    if (NIL_P(RMATCH(match)->regexp)) {
        return rb_hash_new_with_size(0);
    }

    if (NIL_P(keys)) {
        h = rb_hash_new_with_size(onig_number_of_names(RREGEXP_PTR(RMATCH(match)->regexp)));

        struct MEMO *memo;
        memo = MEMO_NEW(h, match, 1);

        onig_foreach_name(RREGEXP_PTR(RMATCH(match)->regexp), match_named_captures_iter, (void*)memo);

        return h;
    }

    Check_Type(keys, T_ARRAY);

    if (onig_number_of_names(RREGEXP_PTR(RMATCH(match)->regexp)) < RARRAY_LEN(keys)) {
        return rb_hash_new_with_size(0);
    }

    h = rb_hash_new_with_size(RARRAY_LEN(keys));

    for (i=0; i<RARRAY_LEN(keys); i++) {
        VALUE key = RARRAY_AREF(keys, i);
        VALUE name;

        Check_Type(key, T_SYMBOL);

        name = rb_sym2str(key);

        int num = NAME_TO_NUMBER(RMATCH_REGS(match), RMATCH(match)->regexp, RMATCH(match)->regexp,
                         RSTRING_PTR(name), RSTRING_END(name));

        if (num >= 0) {
            rb_hash_aset(h, key, rb_reg_nth_match(num, match));
        }
        else {
            return h;
        }
    }

    return h;
}