Use set instead of map<T, bool>
tree5ac4a9d404eee8a0b99fd3e4835b24fc09c2b896
-rw-r--r-- 458 .gitignore
-rw-r--r-- 975 .gitmodules
-rw-r--r-- 639 .mailmap
-rw-r--r-- 231 .tgitconfig
drwxr-xr-x - Languages
-rw-r--r-- 3974 README.md
-rw-r--r-- 2988 appveyor.yml
-rw-r--r-- 6137 architecture.txt
-rw-r--r-- 2756 build.txt
drwxr-xr-x - contrib
drwxr-xr-x - doc
drwxr-xr-x - ext
-rw-r--r-- 952 release.txt
drwxr-xr-x - src
drwxr-xr-x - test