Add Span::first() and Span::last().

absl::Span, base::span, and std::span have first() and last() methods
which give prefixes and suffixes. first() just saves 5 characters, but
last() is nicer to write than subspan() for suffixes.

Unlike subspan(), they also do not have clipping behavior, so we're
guaranteed the length is correct. The clipping behavior comes from
absl::Span::subspan() and is not present in std::span or base::span.
I've left it in, in case we switch to absl::Span in the future, but I
imagine absl::Span will need to migrate this at some point.

Change-Id: I042dd6c566b6d753ec6de9d84e8c09ac7c270267
Reviewed-by: Adam Langley <>
6 files changed
tree: bb51b1761c10616d1fc41534eed1dd0df72e48de
  1. .clang-format
  2. .github/
  3. .gitignore
  7. CMakeLists.txt
  16. codereview.settings
  17. crypto/
  18. decrepit/
  19. fuzz/
  20. go.mod
  21. go.sum
  22. include/
  23. sources.cmake
  24. ssl/
  25. third_party/
  26. tool/
  27. util/


BoringSSL is a fork of OpenSSL that is designed to meet Google's needs.

Although BoringSSL is an open source project, it is not intended for general use, as OpenSSL is. We don't recommend that third parties depend upon it. Doing so is likely to be frustrating because there are no guarantees of API or ABI stability.

Programs ship their own copies of BoringSSL when they use it and we update everything as needed when deciding to make API changes. This allows us to mostly avoid compromises in the name of compatibility. It works for us, but it may not work for you.

BoringSSL arose because Google used OpenSSL for many years in various ways and, over time, built up a large number of patches that were maintained while tracking upstream OpenSSL. As Google's product portfolio became more complex, more copies of OpenSSL sprung up and the effort involved in maintaining all these patches in multiple places was growing steadily.

Currently BoringSSL is the SSL library in Chrome/Chromium, Android (but it's not part of the NDK) and a number of other apps/programs.

Project links:

There are other files in this directory which might be helpful: