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1. No, the grammar is not the issue per se. As you say, C has the same problem, and C code invariably compiles dozens of times faster than C++, and both Zig and

1. No, the grammar is not the issue per se. As you say, C has the same problem, and C code invariably compiles dozens of times faster than C++, and both Zig and Rust have modern grammars, but Zig compiles about as quickly as C and Rust is only somewhat faster than C++ (depending on features used). 2. This is incorrect. What's happening is that each template instantiation for a new set of template arguments requires reprocessing the template to check types and generate code, and also that is done per translation unit instead of per project. Each distinct template instantiation increases the compilation time a bit, much more than it takes to parse the use itself. That's why it's easy to have a small C++ source that takes several seconds to compile.

bsder 3y ago
> 1. No, the grammar is not the issue per se. As you say, C has the same problem, and C code invariably compiles dozens of times faster than C++, and both Zig and Rust have modern grammars, but Zig compiles about as quickly as C and Rust is only somewhat faster than C++ (depending on features used). Sorry, the C++ grammar is terrible. There are lots of things where C++ can't figure out whether something is a class or name or template or constructor call until looking way far down the chain. However, you are the first person I think I have ever heard claim that Rust is faster than C++. Rust is notoriously slow to compile. Zig generally compiles much faster than most C projects I've used. However, that is difficult to lay at the hands of C as a lot of those are the build system being obtuse.
- fluoridation 3y ago
  >Sorry, the C++ grammar is terrible. When did I say otherwise? What I said was that it's not the main cause of C++'s long compilation times. The grammar causes other problems, such as making it more difficult to write parsers for IDEs, and creating things like the most vexing parse. >However, you are the first person I think I have ever heard claim that Rust is faster than C++. Rust is notoriously slow to compile. It's kind of a mixed bag. Given two projects of similar complexity, one in C++ and one in Rust, the one written in Rust will take longer to compile if organized as a single crate, because right now there's no way to parallelize compilation within a single crate. However, compiling the C++ version will definitely be the larger computational task, and would take longer if done in a single thread. Both contain Turing-complete meta-languages, so both can make compiling a fixed length source take an arbitrarily long time. Rust's type system is more complex, but I think C++'s templates win out on computational load. You're running a little dynamically typed script inside the compiler every time you instantiate a template.

bsder 3y ago

> 1. No, the grammar is not the issue per se. As you say, C has the same problem, and C code invariably compiles dozens of times faster than C++, and both Zig and Rust have modern grammars, but Zig compiles about as quickly as C and Rust is only somewhat faster than C++ (depending on features used). Sorry, the C++ grammar is terrible. There are lots of things where C++ can't figure out whether something is a class or name or template or constructor call until looking way far down the chain. However, you are the first person I think I have ever heard claim that Rust is faster than C++. Rust is notoriously slow to compile. Zig generally compiles much faster than most C projects I've used. However, that is difficult to lay at the hands of C as a lot of those are the build system being obtuse.

fluoridation 3y ago
>Sorry, the C++ grammar is terrible. When did I say otherwise? What I said was that it's not the main cause of C++'s long compilation times. The grammar causes other problems, such as making it more difficult to write parsers for IDEs, and creating things like the most vexing parse. >However, you are the first person I think I have ever heard claim that Rust is faster than C++. Rust is notoriously slow to compile. It's kind of a mixed bag. Given two projects of similar complexity, one in C++ and one in Rust, the one written in Rust will take longer to compile if organized as a single crate, because right now there's no way to parallelize compilation within a single crate. However, compiling the C++ version will definitely be the larger computational task, and would take longer if done in a single thread. Both contain Turing-complete meta-languages, so both can make compiling a fixed length source take an arbitrarily long time. Rust's type system is more complex, but I think C++'s templates win out on computational load. You're running a little dynamically typed script inside the compiler every time you instantiate a template.