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“Besides strict typing and having a generally ugly syntax, C++ also requires ahead of time compilation.” What’s wrong with strict typing and ahead of time comp

“Besides strict typing and having a generally ugly syntax, C++ also requires ahead of time compilation.” What’s wrong with strict typing and ahead of time compilation as long as it compiles fast? Doesn’t this prevent many runtime errors that can occur in Python? Python is a higher level language than C++ so it requires less effort but newer compiled/typed languages offer more of what Python is good at

klodolph 4y ago
I have worked with very few C++ projects that compile fast, and my experience is that the errors in C++ projects are often more severe than the errors in Python projects. Even with modern C++ smart pointer style, I’ve seen all sorts of stuff like dangling pointers / use-after-free, buffer overruns, etc. All in code that had been reviewed.
- melling 4y ago
  Yes, C++ was created in the 1980’s and a lot had been added … That’s why I was suggesting newer compiled languages incorporating some of what we’ve learned over the past 4 decades. eg type inference
  - PathOfEclipse 4y ago
    In general, the more work the type system is doing for you, the slower the compilation speed. Kotlin and Scala, for instance, both compile far more slowly than Java. I think even C# compiles very slowly compared to Java. You mention type inference, but type inference actually slows down compilation, and the more sophisticated the type inference, the slower the compilation! Similarly, Rust compilation speed is much slower than GoLang's, whose type system does relatively very little for you. I haven't seen exact numbers, but I've seen people say Rust and C++ have similar compilation speeds, and both are, in general, slow to compile.
    - cestith 4y ago
      Rust gives you so much more for the same compilation speed though.
- tomovo 4y ago
  Try any larger Swift project and suddenly C++ looks pretty fast. Agreed on the pointers though.
- galangalalgol 4y ago
  In my experience a good pipeline with decent unit tests makes c++ and python work fine.
  - ahartmetz 4y ago
    And Valgrind (and / or Memory Sanitizer), they mostly remove a big source of problems in C++ code.
maccard 4y ago
> What’s wrong with strict typing and ahead of time compilation as long as it compiles fast? Doesn’t this prevent many runtime errors that can occur in Python? Nothing, as long as the compilation is fast. C++ compilation is not fast. The large C++ projects I've worked on over the last few years, compilation is bordering on 2 hours for a full build, and 10-60s for incremental builds. At one point, incremental changes were taking 15 minutes to link at one point (resolved by [0]). Go is a great example of fast compilation and strict typing IMO. [0] https://devblogs.microsoft.com/cppblog/improved-linker-fundamentals-in-visual-studio-2019/ https://devblogs.microsoft.com/cppblog/improved-linker-funda...
- Beltalowda 4y ago
  Go was designed, in part, as a response to C++'s slow compile speeds. The Go compiler has gotten a bit slower over the years, but it's still pretty fast, especially when compared to C++ or Rust. > In 2007, build engineers at Google instrumented the compilation of a major Google binary. The file contained about two thousand files that, if simply concatenated together, totaled 4.2 megabytes. By the time the #includes had been expanded, over 8 gigabytes were being delivered to the input of the compiler, a blow-up of 2000 bytes for every C++ source byte. https://go.dev/talks/2012/splash.article#TOC_5 https://go.dev/talks/2012/splash.article#TOC_5. I also hate how just adding some definition to a .h file that's only referenced in one .c (or .cpp) file will recompile loads just because the header file changed. Maybe there's ways to improve on that (ccache?), but I mostly write C to contribute to open source projects (rather than my own) and it can be an annoying wait.
  - snovv_crash 4y ago
    You can limit the impact of this with forward declarations and only putting that is needed for the public API into the header includes. The rest can all live in the .cpp
- the_svd_doctor 4y ago
  C++ (especially template heavy with lots of headers and so on) is certainly not fast to compile. But 2 hours that's crazy. What sort of codebase and on what kind of machine? A 128 cores threadripper is a great workstation to compile C++ code fast :D
agumonkey 4y ago
I see a strong convergence of typed / fast / expressive languages between python/php/ruby and cpp/ada. Rust is one trendy instance but I believe it's gonna create a spot around it.
DeathArrow 4y ago
>Python is a higher level language than C++ so it requires less effort but newer compiled/typed languages offer more of what Python is good at I see Nim as clearly better if you write a larger software. It's a shame it's usage is low and thus there aren't many Nim resources.
- polotics 4y ago
  I think Nim is best placed as the choice for the fast functional core performance-critical and cpu-bound few parts of a larger python codebase.
exabrial 4y ago
> What’s wrong with strict typing and ahead of time compilation as long as it compiles fast? Doesn’t this prevent many runtime errors that can occur in Python? Nothing, it's all good things: It's easier to write, easier to debug, and the compiler (not the user) catches bugs.
wiseowise 4y ago
C++ compilation is anything but fast.

klodolph 4y ago

I have worked with very few C++ projects that compile fast, and my experience is that the errors in C++ projects are often more severe than the errors in Python projects. Even with modern C++ smart pointer style, I’ve seen all sorts of stuff like dangling pointers / use-after-free, buffer overruns, etc. All in code that had been reviewed.

melling 4y ago
Yes, C++ was created in the 1980’s and a lot had been added … That’s why I was suggesting newer compiled languages incorporating some of what we’ve learned over the past 4 decades. eg type inference
- PathOfEclipse 4y ago
  In general, the more work the type system is doing for you, the slower the compilation speed. Kotlin and Scala, for instance, both compile far more slowly than Java. I think even C# compiles very slowly compared to Java. You mention type inference, but type inference actually slows down compilation, and the more sophisticated the type inference, the slower the compilation! Similarly, Rust compilation speed is much slower than GoLang's, whose type system does relatively very little for you. I haven't seen exact numbers, but I've seen people say Rust and C++ have similar compilation speeds, and both are, in general, slow to compile.
  - cestith 4y ago
    Rust gives you so much more for the same compilation speed though.
tomovo 4y ago
Try any larger Swift project and suddenly C++ looks pretty fast. Agreed on the pointers though.
galangalalgol 4y ago
In my experience a good pipeline with decent unit tests makes c++ and python work fine.
- ahartmetz 4y ago
  And Valgrind (and / or Memory Sanitizer), they mostly remove a big source of problems in C++ code.

maccard 4y ago

> What’s wrong with strict typing and ahead of time compilation as long as it compiles fast? Doesn’t this prevent many runtime errors that can occur in Python? Nothing, as long as the compilation is fast. C++ compilation is not fast. The large C++ projects I've worked on over the last few years, compilation is bordering on 2 hours for a full build, and 10-60s for incremental builds. At one point, incremental changes were taking 15 minutes to link at one point (resolved by [0]). Go is a great example of fast compilation and strict typing IMO. [0] https://devblogs.microsoft.com/cppblog/improved-linker-fundamentals-in-visual-studio-2019/ https://devblogs.microsoft.com/cppblog/improved-linker-funda...

Beltalowda 4y ago
Go was designed, in part, as a response to C++'s slow compile speeds. The Go compiler has gotten a bit slower over the years, but it's still pretty fast, especially when compared to C++ or Rust. > In 2007, build engineers at Google instrumented the compilation of a major Google binary. The file contained about two thousand files that, if simply concatenated together, totaled 4.2 megabytes. By the time the #includes had been expanded, over 8 gigabytes were being delivered to the input of the compiler, a blow-up of 2000 bytes for every C++ source byte. https://go.dev/talks/2012/splash.article#TOC_5 https://go.dev/talks/2012/splash.article#TOC_5. I also hate how just adding some definition to a .h file that's only referenced in one .c (or .cpp) file will recompile loads just because the header file changed. Maybe there's ways to improve on that (ccache?), but I mostly write C to contribute to open source projects (rather than my own) and it can be an annoying wait.
- snovv_crash 4y ago
  You can limit the impact of this with forward declarations and only putting that is needed for the public API into the header includes. The rest can all live in the .cpp
the_svd_doctor 4y ago
C++ (especially template heavy with lots of headers and so on) is certainly not fast to compile. But 2 hours that's crazy. What sort of codebase and on what kind of machine? A 128 cores threadripper is a great workstation to compile C++ code fast :D

agumonkey 4y ago

I see a strong convergence of typed / fast / expressive languages between python/php/ruby and cpp/ada. Rust is one trendy instance but I believe it's gonna create a spot around it.

DeathArrow 4y ago

>Python is a higher level language than C++ so it requires less effort but newer compiled/typed languages offer more of what Python is good at I see Nim as clearly better if you write a larger software. It's a shame it's usage is low and thus there aren't many Nim resources.

polotics 4y ago
I think Nim is best placed as the choice for the fast functional core performance-critical and cpu-bound few parts of a larger python codebase.

exabrial 4y ago

> What’s wrong with strict typing and ahead of time compilation as long as it compiles fast? Doesn’t this prevent many runtime errors that can occur in Python? Nothing, it's all good things: It's easier to write, easier to debug, and the compiler (not the user) catches bugs.

wiseowise 4y ago

C++ compilation is anything but fast.