tree f2187c41f32fec8bf002ffe5be437be472d936de
parent 5a982a6dba7c4d98b443471823be0bd9d9677143
author Paul Wankadia <junyer@google.com> 1552894266 -0700
committer Paul Wankadia <junyer@google.com> 1552894556 +0000

Get rid of `using std::string;`. (part 1 of N)

Change-Id: I315e5e6bf1281ec252e68ab4e50357852e75e0ea
Reviewed-on: https://code-review.googlesource.com/c/re2/+/39110
Reviewed-by: Paul Wankadia <junyer@google.com>