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Show HN: C++11 immutable string

by syvex on 6/4/14, 4:59 AM with 6 comments

I'm looking for feedback on this approach to an immutable string (istring). The idea is to provide a super fast immutable string that can be efficiently passed to lambdas as well as be 100% thread safe.

Another bonus is faster hashing. If a string literal is given to istring, then the hash is computed at compile time! Other strings will have their hashes cached for later use. The istring is designed more or less after the python string in this regard.

It should also consume less memory than std::string and perform faster in all other areas.

  • by Nican on 6/4/14, 8:18 AM

    Just as a note, on Java 7, developers opted for not having a single buffer backing multiple strings due to the backing references never been deleted. [1] [2]

    [1] http://stackoverflow.com/questions/16123446/java-7-string-su...

    [2] http://www.reddit.com/r/programming/comments/1qw73v/til_orac...

  • by thegeomaster on 6/4/14, 7:40 AM

    Great job. I like it how peole are moving to and developing for C++11 as I think it's a huge step forward in the standard. The one cosmetic complaint I have is that the slicing syntax is not verbose enough for my taste. Also, what hash algo did you use? Asking just out of curiosity. I remember running a benchmark a long ago of different non-cryptographic hashes. The collision resistance was pretty consistent across all of them, but some were really slow and some were really fast, and that could directly affect the performance on hashtables and other structures that rely on hashes.