Readme.msvs.md

Explanation of this project

Low token count C++ 20 VS2019 headers

Each of these is in the bottom quartile of token parse times for all STL headers:

• cassert
• cctype
• cerrno
• cfenv
• cfloat
• cinttypes
• ciso646
• climits
• clocale
• compare
• csetjmp
• csignal
• cstdalign
• cstdarg
• cstdbool
• cstddef
• cstdint
• cstring
• ctime
• cuchar
• cwctype
• initializer_list
• version

Note that cstdlib and cstdio are not in this list. They have become rather fatter, relatively speaking, in VS2019.

Lowest token count C++ 20 VS2019 containers

All apart from <array> now have a low token count in VS2019.

Highest token count C++ 20 VS2019 headers

You may wish to avoid using these headers if compile times are very important to you:

• array
• ccomplex
• codecvt
• complex
• ctgmath
• execution
• filesystem
• fstream
• functional
• future
• iomanip
• ios
• iostream
• istream
• iterator
• locale
• ostream
• random
• ranges
• regex
• sstream
• strstream

Highest token count C++ 20 VS2019 containers

You may wish to avoid using these containers if compile times are very important to you:

• array

This is expected to be fixed in VS2020.

Surprising high token count C++ 20 VS2019 headers

I found these headers have much higher token count than you'd expect.

• atomic
  • Cause: Drags in a lot of other headers. I can't see why when libstdc++ doesn't do this.
  • https://github.com/ned14/stl-header-heft/blob/master/msvs-2019/atomic.csv
• array
  • Cause: Drags in a lot of other headers, including <algorithm>, <iterator>, <istream>, <ostream>, <stdexcept> and so on. I can't see why when libstdc++ doesn't do this.
  • https://github.com/ned14/stl-header-heft/blob/master/msvs-2019/array.csv
• complex
  • Cause: Drags in a lot of other headers, including <sstream>, <string>, <istream>, <ostream>, <stdexcept> and so on. libstdc++ is just as bad.
  • https://github.com/ned14/stl-header-heft/blob/master/msvs-2019/complex.csv