alt Hacker NewsExpected a rant, got a life-pro-tip. Enough for a good happy new year.
That said, we can abuse the same trick for any languages that treats `//` as comment.
List of some practical(?) languages: C/C++, Java, JavaScript, Rust, Swift, Kotlin, ObjC, D, F#, GLSL/HLSL, Groovy
Personally, among those languages, GLSL sounds most interesting. A single-GLSL graphics demo is always inspiring. (Something like https://www.shadertoy.com/ )
Also, let’s not forget that we can do something similar using block comment(`/* … */`). An example in C:
/*/../usr/bin/env gcc "$0" "$@"; ./a.out; rm -vf a.out; exit; */
#include <stdio.h>
int main() { printf("Hello World!\n"); return 0; }
Replies
For C/++ just use "#!". When TCC first came out, we used this exact technique for "C scripting". It requires a dirty SO methodology (you can't really control linking well).
For larger projects (the exe), the shebang points to a C build file, which when compiled, knows the root path; that C build script then looks for a manifest, builds, links, and fork()s. A good a/m timestamp library with direct ccache support can spin up as fast as a script even on big projects.
Again, this is all a bad idea bc it's hard to control your environment.
I guess we were doing all this in the mid 2000s? When did TCC come out?
You don't need to abuse comments like this for Rust, because it supports shebangs directly.
For Swift there’s even a project[1] that allows running scripts that have external dependencies (posting the fork because the upstream is mostly dead).
I think it’s uv’s equivalent, but for Swift.
(Also Swift specifically supports an actual shebang for Swift scripts.)
[1] https://github.com/xcode-actions/swift-sh