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Comment by chubot | Hacker News Reader

They should really be using bash for this, not make. There is nothing wrong with bash scripts calling Make -- for building with DEPENDENCIES. But when you aren't doing that, just use bash (because Make is actually Make + bash to begin with).

This is dumb:

    restart-frontend: ## Restart the frontend and admin apps in dev
       @make stop-frontend-dev && make run-frontend-dev
       @echo "Frontend app restarted"

Write it with a shell script like this:

    stop-frontend-dev() {
       ...
    }

    run-frontend-dev() {
       ...
    }

    restart-front-end() {
      stop-frontend-dev
      run-frontend-dev
      echo "Frontend app restarted"
    }
  
    build() {
       make  # this actually does stuff you can't do in bash.
    }

    "$@"  # call function $1 with args $2...  Can also print help here.

This is a lot cleaner. The PID stuff can be done with bash too.

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This is only cleaner in your simple case. Make's power lies in dependency tracking and its declarative approach to defining those dependencies.

When you use make anyway, adding those targets there is the logical thing to do. One interface instead of two. It's even less lines of code than your proposed solution (which btw does not fail hard like make does, so a recipe for desaster).

Finally: Pretty please, sh, not bash. Almost none of the bash-scripts out there use actual bash-features and those that do can usually easily be rewritten to just rely on a plain posix shell.

For makefiles, even GNU make executes commands using /bin/sh (unless you set $(SHELL) explicitly); trouble is, many Linux systems use bash for /bin/sh, and its sh emulation is lacking.

My point is precisely that the script is not using "Make's power in dependency tracking". It's just running commands. If you need Make, use Make; otherwise use shell. It's far from unusual to have a Makefile and some shell scripts at the top level of a project.

Make's semantics are to invoke the shell at EVERY LINE. This is slow and makes quoting a nightmare (try quoting find or sed in bash in Make correctly; you cannot directly invoke them from Make). Conversely, bash's semantics do not involve make whatsoever :)

Shell also has local variables for modularity, and better constructs for conditionals and iterations. And functions. Make has a poor man's implementation of Turing-complete constructs compared to shell (which is a little ironic since shell is already sort of a poor man's procedural language).

'set -o errexit' makes bash fail on errors. Also, as mentioned, the Makefile isn't using phony targets. Neither shell or Make is perfect, but shell is the more appropriate tool when you're not making use of Make's incremental build features.

Another pattern I find useful is to have the actions take more arguments, like:

    ./run.sh dev-frontend --flag-for-testing

which is implemented just like this:

    dev-front-end() {
      ./frontend.py --port 8080 --other-default-flag "$@"
    }
    "$@"

The arguments to Make are actually TARGETS/files and not functions, so I don't think you can do this.

> Make's semantics are to invoke the shell at EVERY LINE. This is slow [...]

I assume you mean commands here? Actually, how slow is it? Ever measured it? I am sure me writing this line took more time than they could save by a rewrite over the course of a few years of using the performance optimized version.

> Shell also has local variables for modularity, and better constructs for conditionals and iterations

And variables in make that you set for a command are only visible to it. Besides - wasn't your point that the OP should not use make because s/he does not use its features?

> 'set -o errexit' makes bash fail on errors

Indeed it does, it was just missing from your better version.

> Another pattern I find useful is to have the actions take more arguments [...] The arguments to Make are actually TARGETS/files and not functions, so I don't think you can do this.

Yes, one communicates with make through variables, not through arguments.

Over the last 20 or so years I've done my fair share of shell scripting and of writing makefiles. Maybe I am just too old and boring to get excited over this, but let me recap: The OP happens to be using make, s/he used an elegant hack to have the file document itself and its usage. S/He wrote about the latter. No, I am not impressed by the post - I used a similar technique in 2003 or 2004 to bootstrap the documentation of a very complex build system - and I'm sure others have before and after me. But I like the concise article.

Debating whether make is "better" than "sh" is completely off-topic here - if there was a universal truth we'd not have seen tools like psh, scsh and the rest of language-specific shell substitutes nor would we have the myriad of language-specific build tools. Back then, when I was young and naive, I've implemented a few of those myself. But now I am not young anymore. And now I naively believe that people should use what they are most productive with. Or everybody come to their senses and just use lisp.

Before fig, Docker build repositories often have awkward arguments to build or run a container, and that's where I first saw people using a Makefile as basically a bash script file. I copied it and since then I've used it like 100 times since, it feels a lot more easier than the above bash script approach, though for reasons I can't quite put into words right now.

It also turns out that dependencies creep up pretty often, so shortly after we started abusing the Makefile, we also started using it "right" too.

Examples: * https://github.com/dergachev/screengif/blob/master/Makefile * https://github.com/dergachev/drupal-docker-marriage/blob/mas...

Nope, to me it isn't cleaner. Also, make has "make -n" which is absolutely golden.

It's not about which script file is considered to be "cleaner", aesthetic preferences don't matter here.

The Makefile here almost certainly has some unexpected side-effects when used in a way that the original author didn't intend to. E.g. accidentally removing your PID files (e.g. with git clean) and then you have more than one dev server running.

Make isn't intended for starting/stopping services or doing non-build tasks. It really sucks for that kind of tasks. It might work ok for the handful of workflows the author intended it for, but then spectacularly break down when someone else tries to do something outside of that or when new features get added.

Sometimes I see people use Make for situations where some build platform (e.g. Windows or an embedded toolchain) doesn't have a proper shell at hand. But it's still not a great idea to use Makefiles as a replacement for shell scripts.

There are much better alternatives for doing non-build tasks.

What problems would there be doing things from GNU make, that there wouldn't be when doing the same thing from a shell script?

My experience has been that you can totally use GNU make as a replacement for shell scripts, and it works fine. Why wouldn't it? It's just sequences of shell commands, where each sequence has a name.

And in fact for this sort of situation, where you've got one of a pre-canned set of sequences to run, it works very well - because GNU make will handle the command line for you, and most shells will give you some kind of basic (but usable) tab completion for the sequences available, without any effort on your part.

You do need to use phony targets, though. (https://www.gnu.org/software/make/manual/html_node/Phony-Tar...) This might seem like a ridiculous requirement, but I've seen plenty of bash scripts that just kept on going when a shell command failed; it's not like GNU make is unique in requiring a small amount of boilerplate to make things work nicely.

I was replying to this line

> This is a lot cleaner. The PID stuff can be done with bash too.

In any case, until there is a tool which is as ubiquitous and as declarative as make you're going to have hard time convincing those of use who use it this way to stop.

It is... It's alway better to write code that shows the intent. When you add comments you force other dev to maintain them, and if they don't you will end up with obsolete or incorrect comments.

Plus, you end up doing stupid stuff like:

DoThat(); // It does that

Bit of a tangent, but in a fit of snark a few years ago I wrote a bash "task runner" in the vein of Grunt and Make:

http://manuel.00null.net/

Not very useful, but it kept me amused for a weekend at least.

But why does it matter? With your solution they'll have two "task files" to manage instead of one.

Because make is for managing dependencies, which it tracks by files, as soon as you need to do something which doesnt leave files around, such as start a new service, you then need to plug this hole, by using "touch" and leaving files around, which this example doesnt do so it may actually leave the system inconsistent and make the makefile do things it shouldnt, thus causing errors difficult to diagnose. But then you run into the problem of making make have functions of a service manager, which it isnt, and you will most likely fail doing that.

Use Make when you need to track dependencies based on files, such as for build systems whose output is files, and bash/other script for managing a hosts services which are/may be required for the build system.

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