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by nazgul17 115 days ago
Trying to be language agnostic: it should be as self-explanatory as possible. 2>&1 is all but.

Why is there a 2 on the left, when the numbers are usually on the right. What's the relationship between 2 and 1? Is the 2 for std err? Is that `&` to mean "reference"? The fact you only grok it if you know POSIX sys calls means it's far from self explanatory. And given the proportion of people that know POSIX sys calls among those that use Bash, I think it's a bit of an elitist syntax.
1 comments
stephenr 114 days ago
POSIX has a manual for shell. You can read 99% of it without needing to know any syscalls. I'm not as familiar with it but Bash has an extensive manual as well, and I doubt syscall knowledge is particularly required there either.

If your complaint is "I don't know what this syntax means without reading the manual" I'd like to point you to any contemporary language that has things like arrow functions, or operator overloading, or magic methods, or monkey patching.

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nazgul17 114 days ago
No, the complaint is that "the syntax is not intuitive even knowing the simpler forms of redirection": this one isn't a competition of them, but rather an ad-hoc one.

I know about manuals, and I have known this specific syntax for half of my life.

Arrow functions etc are mechanisms in the language. A template you can build upon. This one is just one special operator. Learn it and use it, but it will serve no other purpose in your brain. It won't make anything easier to understand. It won't help you decipher other code. It won't help you draw connections.

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stephenr 114 days ago
> the syntax is not intuitive even knowing the simpler forms of redirection

The MDN page for arrow functions in JS has, I shit you not, 7 variations on the syntax. And your complaint is these are not intuitively similar enough?

call > output

call 2>&1

call > output 2> error

call 1> output 2> error

Give me a fucking break.

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