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Nice that these exist—but does anyone else absolutely abhor shell programming? The syntax is impossible to memorize, it’s incredibly easy to make mistakes, and debugging is a pain. I hate it more than C++ and AppleScript.
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They suggest that based on their experience. Error handling in bash is awful so I advice against using it for anything complex.
Anything complex should be written in a competent language like Java. Script languages (like Bash and Python) are for short (a few lines long) scripts. Using the tool outside the scope of what it was designed for is not a good idea.
I mean, viewing Python strictly as a scripting language? I am honestly lost for words. There are many huge and major applications and web sites written in Python, without people regretting it after the fact. And yet here you are dismissing it out of hand without a single argument.
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Just use the included zsh.
I like my scripts to run on both linux and macos. It's somewhat limiting, but it saves trouble.
One thing that has bitten me in the past is that, if you declare your associative arrays within a function, that associative array is ALWAYS global. Even if you declare it with `local -A` it will still be global. Despite that, you cannot pass an associative array to a function by value. I say "by value" because while you can't call `foo ${associative_array}` and pick it up in foo with `local arg=$1, you can pass it "by reference" with `foo associative_array` and pick it up in foo with `local -n arg=$1`, but if you give the passed in dereferenced variable a name that is already used in the global scope, it will blow up, eg `local -n associative_array=$1`.
As a general rule for myself when writing bash, if I think one of my colleagues who has an passable knowledge of bash will need to get man pages out to figure out what my code is doing, the bash foo is too strong and it needs to be dumbed down or re-written in another language. Associative arrays almost always hit this bar.
Earlier quoted context omitted.
They suggest that based on their experience. Error handling in bash is awful so I advice against using it for anything complex.
Anything complex should be written in a competent language like Java. Script languages (like Bash and Python) are for short (a few lines long) scripts. Using the tool outside the scope of what it was designed for is not a good idea.
I advocate the following rules for when to write and when not to write a shell script. # Write a shell script: * Heavy lifting done by powerful tool (sort, grep, curl, git, sed, find, …) * Script will glue diverse tools * Workflow resembles a pipeline * Steps can be interactively developed as shell commands * Portability * Avoid dependency hell * One-off job # Avoid shell scripting: * Difficult to see the preceding p…
So this has inspired me to Ask HN, I’m getting ready to post it with a reference to this discussion, but thought I’d start here: does anyone know of a good resource for learning Python (or Go, Perl…any good small project/scripting/solo hacking languages) that’s tailored for folks who already have a good foundation in shell scripting, markup, config/infra automation, build tools, etc.? I’m open to books, web-based tutorials, apps, or just good examples for studying.
I’m open to the notion that I simply haven’t put in the work, and powered through the doldrums of novice tutorials far enough to get to where the meaty stuff is. Worst case, I’m a big fan of taking courses at the local community college for my own edification, absent any specific degree program or professional certification. It would still necessitate a lot of remedial/redundant steps, but I can always help others through those chapters while filling in any of my own gaps. Day-to-day, I generally work alone, but I find such things are easier with others to help motivate and focus my efforts. Perhaps I have answered my own question, but even still, I appreciate any advice/recommendations folks might have.
I advocate the following rules for when to write and when not to write a shell script. # Write a shell script: * Heavy lifting done by powerful tool (sort, grep, curl, git, sed, find, …) * Script will glue diverse tools * Workflow resembles a pipeline * Steps can be interactively developed as shell commands * Portability * Avoid dependency hell * One-off job # Avoid shell scripting: * Difficult to see the preceding p…
I’ve been a sysadmin for nearly a decade, a frontend web designer for much longer (I still have a book on all the exciting changes in HTML4), and while I can very easily learn, compose, and use many markup and scripting languages, I have always struggled with full-on programming languages, and I’m not exactly sure why. Part of it, I think, is that most tutorials and online learning resources are focused on novices wh…
If anyone else is interested, this thread from 2020 is where I am starting, it seems to align with my own quest pretty well: https://news.ycombinator.com/item?id=22932794
Oh dear. I've been trying to get people to not use this feature for a while. One thing that has bitten me in the past is that, if you declare your associative arrays within a function, that associative array is ALWAYS global. Even if you declare it with `local -A` it will still be global. Despite that, you cannot pass an associative array to a function by value. I say "by value" because while you can't call `foo ${as…
#!/bin/bash
declare -A map1=([x]=2)
echo "1. Global scope map1[x]: ${map1[x]}"
func1() {
echo " * Enter func1"
local -A map1
map1[x]=3
echo " Local scope map1[x]: ${map1[x]}"
}
func1
echo "2. Global scope map1[x]: ${map1[x]}"
1. Global scope map1[x]: 2
* Enter func1
Local scope map1[x]: 3
2. Global scope map1[x]: 2I advocate the following rules for when to write and when not to write a shell script. # Write a shell script: * Heavy lifting done by powerful tool (sort, grep, curl, git, sed, find, …) * Script will glue diverse tools * Workflow resembles a pipeline * Steps can be interactively developed as shell commands * Portability * Avoid dependency hell * One-off job # Avoid shell scripting: * Difficult to see the preceding p…
I’ve been a sysadmin for nearly a decade, a frontend web designer for much longer (I still have a book on all the exciting changes in HTML4), and while I can very easily learn, compose, and use many markup and scripting languages, I have always struggled with full-on programming languages, and I’m not exactly sure why. Part of it, I think, is that most tutorials and online learning resources are focused on novices wh…
Learning Go by Jon Bodner is a good choice. It seems to assume that Go is the reader's second (or tenth) language.
Earlier quoted context omitted.
Anything complex should be written in a competent language like Java. Script languages (like Bash and Python) are for short (a few lines long) scripts. Using the tool outside the scope of what it was designed for is not a good idea.
Tell me you have never seriously used Python without telling me you have never seriously used Python. I mean, viewing Python strictly as a scripting language? I am honestly lost for words. There are many huge and major applications and web sites written in Python, without people regretting it after the fact. And yet here you are dismissing it out of hand without a single argument.
Further down is a comment about that: https://news.ycombinator.com/item?id=42664939