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Forbidding unused imports was a direct response to the practical difficulty of compiling google-scale C++ binaries: https://go.dev/talks/2012/splash.article#TOC

by riwsky 2y ago

Forbidding unused imports was a direct response to the practical difficulty of compiling google-scale C++ binaries: https://go.dev/talks/2012/splash.article#TOC_5 https://go.dev/talks/2012/splash.article#TOC_5. In theory, programmers can just be disciplined enough or set up CI lints for unused imports. In practice…

swiftcoder 2y ago
I'm sure the rest of us all benefit from arcane doctrine required to scale up a 25,000 engineer, 40,000 commit/day monorepo.
- throwawaymaths 2y ago
  You do. The zig compiler and stdlib can iterate faster across a team of mostly by numbers volunteer developers with varying degrees of skill and across global timezones because of the discipline that the compiler imposes.
em-bee 2y ago
i prefer a language that doesn't even need to declare imports. why can't the compiler figure them out on its own?
- 8n4vidtmkvmk 2y ago
  I think you're being sarcastic, but ambiguity is the obvious answer. Your IDE can help you resolve these though.
  - em-bee 2y ago
    i am absolutely serious. pike for example does not need imports. if a reference is not found in the local namespace the compiler will find it in the module path and resolve it by itself. there is no ambiguity because each module has a unique name. we accept type inference but don't do the same for module references? why? pike does have an import statement, but its effect is to include all members of a module into the namespace instead of just resolving the ones that are really used. and instead of speeding things up, using import on modules with lots of members may actually slow things down because the namespace is loaded up with lots of unused references. sometimes import is used to help readability, but that's rarely needed because you can solve the same with a simple assignment to a variable. if you can show me an example where import resolves an ambiguity, i'll try to show how pike solves the problem without import.
    - 8n4vidtmkvmk 2y ago
      I don't know how it works in Zig. In JavaScript, you can have lots of things with the same name, so you need to explicitly import them and you can give them an alias at the same time if there's a clash. I believe Python is the same. In C++, you have to #include the thing you want to use somewhere, not necessarily in the same file you use it, it just has to end up in the same compilation unit. If two files define the same name, you'll end up with a compilation error. In very large projects, sometimes you won't notice this until some transitive dependency includes the other thing. I'm personally a fan of explicit imports. I imagine this helps IDEs resolve references without having to scan 1000s of files to resolve them, and it helps build tools pull in only the needed files. Regarding speed (of execution), in JS we have tree-shaking so if you import a file but don't use all of its members, those excess/used members will be dropped from the final bundle (saving on both bundle size and run-time parsing). Plus it means I don't have to spend much time thinking of a super/globally unique name for every thing I define.
      - em-bee 2y ago
        in python every module has a unique name: import math foo = math.pi the compiler can obviously find math in the import statement. why can't it find math.pi directly? pike can.
        8n4vidtmkvmk 2y ago
        If you use fully qualified statements everywhere, sure. That means writing `datetime.datetime.now()` everywhere instead of `from datetime import datetime` and then just doing `datetime.now()`. But then you'll tell me, just create an alias, `dt = datetime.datetime`. Sure, I guess, but now you've made `datetime` some kind of superglobal so you can't use that as a variable anywhere. And how does this work in practice? In Python and JS you can also put executable code inside your modules that gets executed the first time it's imported. Are you telling me that that's going to run the first time it's implicitly imported instead? Is that a good idea? The story in JS gets even crazier because you can do all kinds of whacky things with imports, like hooking up "loaders" so you can import things that aren't even JavaScript (images, CSS, you name it), or you can modify the resolution algorithm.
Phil_Latio 2y ago
This is nonsense argument, because there are more pragmatic solutions: Turn warnings into errors for release builds, or if there is only one build type, have a policy that requires developers to remove all warnings before committing code.

by riwsky 2y ago

swiftcoder 2y ago

I'm sure the rest of us all benefit from arcane doctrine required to scale up a 25,000 engineer, 40,000 commit/day monorepo.

throwawaymaths 2y ago
You do. The zig compiler and stdlib can iterate faster across a team of mostly by numbers volunteer developers with varying degrees of skill and across global timezones because of the discipline that the compiler imposes.

em-bee 2y ago

i prefer a language that doesn't even need to declare imports. why can't the compiler figure them out on its own?

8n4vidtmkvmk 2y ago
I think you're being sarcastic, but ambiguity is the obvious answer. Your IDE can help you resolve these though.
- em-bee 2y ago
  i am absolutely serious. pike for example does not need imports. if a reference is not found in the local namespace the compiler will find it in the module path and resolve it by itself. there is no ambiguity because each module has a unique name. we accept type inference but don't do the same for module references? why? pike does have an import statement, but its effect is to include all members of a module into the namespace instead of just resolving the ones that are really used. and instead of speeding things up, using import on modules with lots of members may actually slow things down because the namespace is loaded up with lots of unused references. sometimes import is used to help readability, but that's rarely needed because you can solve the same with a simple assignment to a variable. if you can show me an example where import resolves an ambiguity, i'll try to show how pike solves the problem without import.
  - 8n4vidtmkvmk 2y ago
    I don't know how it works in Zig. In JavaScript, you can have lots of things with the same name, so you need to explicitly import them and you can give them an alias at the same time if there's a clash. I believe Python is the same. In C++, you have to #include the thing you want to use somewhere, not necessarily in the same file you use it, it just has to end up in the same compilation unit. If two files define the same name, you'll end up with a compilation error. In very large projects, sometimes you won't notice this until some transitive dependency includes the other thing. I'm personally a fan of explicit imports. I imagine this helps IDEs resolve references without having to scan 1000s of files to resolve them, and it helps build tools pull in only the needed files. Regarding speed (of execution), in JS we have tree-shaking so if you import a file but don't use all of its members, those excess/used members will be dropped from the final bundle (saving on both bundle size and run-time parsing). Plus it means I don't have to spend much time thinking of a super/globally unique name for every thing I define.
    - em-bee 2y ago
      in python every module has a unique name: import math foo = math.pi the compiler can obviously find math in the import statement. why can't it find math.pi directly? pike can.
      - 8n4vidtmkvmk 2y ago
        If you use fully qualified statements everywhere, sure. That means writing `datetime.datetime.now()` everywhere instead of `from datetime import datetime` and then just doing `datetime.now()`. But then you'll tell me, just create an alias, `dt = datetime.datetime`. Sure, I guess, but now you've made `datetime` some kind of superglobal so you can't use that as a variable anywhere. And how does this work in practice? In Python and JS you can also put executable code inside your modules that gets executed the first time it's imported. Are you telling me that that's going to run the first time it's implicitly imported instead? Is that a good idea? The story in JS gets even crazier because you can do all kinds of whacky things with imports, like hooking up "loaders" so you can import things that aren't even JavaScript (images, CSS, you name it), or you can modify the resolution algorithm.

Phil_Latio 2y ago

This is nonsense argument, because there are more pragmatic solutions: Turn warnings into errors for release builds, or if there is only one build type, have a policy that requires developers to remove all warnings before committing code.