This page is a snapshot from the LWG issues list, see the Library Active Issues List for more information and the meaning of Resolved status.

1453. Default constructed match_results behavior for certain operations

Section: 28.6.9.5 [re.results.acc] Status: Resolved Submitter: BSI Opened: 2010-08-25 Last modified: 2016-01-28

Priority: Not Prioritized

View all other issues in [re.results.acc].

View all issues with Resolved status.

Discussion:

Addresses GB-126

It's unclear how match_results should behave if it has been default-constructed. The sub_match objects returned by operator[], prefix and suffix cannot point to the end of the sequence that was searched if no search was done. The iterators held by unmatched sub_match objects might be singular.

[ Resolution proposed by ballot comment: ]

Add to match_results::operator[], match_results::prefix and match_results::suffix:
Requires: !empty()

[ 2010-10-24 Daniel adds: ]

Accepting n3158 would solve this issue.

Proposed resolution:

Addressed by paper n3158.