garethrowlands
Joined 8 years ago
Joined 8 years ago
> the goodness of language for long code is inversely proportional to how nice it is for shell one-liners
Well, except for this bit. Oil or fish and awk are perfectly fine for one liners but don't repeat the mistakes of posix shell syntax.
my $x = if ($cond) { 1 } else { 2 }; # Syntax error
Because of this, Perl introduces a second syntax to plug the gap: my $x = $cond ? 1 : 2;
That expression is neither obtuse nor hard to read.Something like the code below is hard to read:
my $fee =
$is_member
? ($is_student ? $student_member_fee : $member_fee)
: ($is_student ? $student_fee : $standard_fee);
It's equivalent to the following code that uses `if`: my $fee;
if ($is_member) {
if ($is_student) {
$fee = $student_member_fee;
}
else {
$fee = $member_fee;
}
}
else {
if ($is_student) {
$fee = $student_fee;
}
else {
$fee = $standard_fee;
}
}
But ideally you would want to write this: my $fee =
if ($is_member) {
if ($is_student) {
$student_member_fee
}
else {
$member_fee
}
}
else {
if ($is_student) {
$student_fee
}
else {
$standard_fee
}
};
Though, of course, perl5 doesn't allow that.Your company likely started using bash before python was ubiquitous.
> Old doesn't imply arcane.
Indeed so. For example, awk is about the same age but doesn't suffer the same problems.
> the shell syntax was never meant to be anything like a systems or application programming language
A programmable shell is not only like a programming language, it is a programming language. Systems tasks have some specialised requirements but, overall, scripting is programming. There is nothing in the problem domain that requires the posix string-substitution problems.
If fish or oil had existed back then, they would likely have won, since they are better.
...
I have analysed your idiomatic one-liner and propose adding the following 30 lines into the application Yes/Yes and always accept such idiocy/No
ESCAPE ESCAPE
/clear
I want to update my powershell skill so that it writes idiomatic pipelines and does not introduce idioms from other languages.
[PASTES overeagerness wording from Claude prompting best practices]
Programmable shells are, in fact, for programming. That posix shell syntax makes it impractical for meaningfully large scripts is something you just accept. And, realistically, it is something you have to accept.
Minimalism isn't why posix shell syntax is bad. For example, awk and jq are minimal but don't make the same mistakes.
Powershell was never designed to be your system shell (Windows doesn't really rely on one) but the main reason it can't be the shell is startup time, which rules it out of wrapper scripts. Its having lots of features might contribute to that but it's not the problem per se (being built on .net is the reason - that and startup time not really mattering on windows). Its lacking the syntax problems of posix shells is very much not a problem. Powershell's error handling is just fine, by the way.
The startup time of even pwsh is too slow to be usable in many scenarios.
PowerShell's not going to be the system shell on your *nix box but it wasn't designed to be. But your posix shell isn't the system shell because it's better. It's pretty much the ultimate expression of worse is better.
That's why there's an industry of alternatives without the faults, such as oil, elvish, fish, nushell. And why awk is so popular.