mycmd VS ShellCheck

Woah, this is very cool. I may try to adopt this.

I recently discovered, similar to the author of the post for this thread, that local variables are dynamically scoped.

I have been writing a lot more shell scripts lately, using a "library" [1] of sorts I've been writing. When I was debugging one of my scripts that uses mycmd, I discovered that I had failed to declare some of my variables local and they were leaking out to the global scope.

I had recently added functionality to call a set of functions on script exit, so I added something that would output the defined variables, in hopes that I could write something that will output them at the beginning and then the end and show the difference. I was surprised when variables defined in my dispatch function [2] for those at exit functions were showing up, even though they were definitely defined as local. It was then that I dug around and discovered the dynamic scope of variables.

I've been trying to figure out how to accomplish what I desire but exclude those variables from calling functions. I haven't been able to find an obvious way to see if the variable is coming from a calling function. I might be able to use techniques like you've pointed out in your linked post to add the tracing that I want. Still need to think more on this.

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[1] https://github.com/travisbhartwell/mycmd

These projects use Caddy as my local development server, Dart Sass for converting my Sass files to CSS, elm, elm-format, elm-optimize-level-2, elm-review, elm-test (only in Calculator), ShellCheck to find bugs in my shell scripts, and Terser to mangle and compress JavaScript code.

ncurse, dialog, zenity[2]. i/o buffering may be an issue [3a,3b]

Assuming using same account, use history command to show past commands[0a, 0b]

'load random example' on shellcheck using own custom examples from history command.[1]

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[3a] : http://www.gnu.org/software/coreutils/manual/html_node/stdbu...

[3b] : http://unix.stackexchange.com/questions/25372/how-to-turn-of...

[2] : http//funprojects.blog/2021/01/25/zenity-command-line-dialogs/

[1] : http://www.shellcheck.net/

[0a] : http://www.tecmint.com/history-command-examples/

[0b] : http://www.tecmint.com/remember-linux-commands/

web based documentation: https://www.tecmint.com/linux-commands-cheat-sheet/

commands grouped by typical usage patterns : https://www.tecmint.com/essential-linux-commands/

... #************************** Terraform ************************************* ARG TERRAFORM_VERSION=1.7.3 RUN set -ex \ && curl -O https://releases.hashicorp.com/terraform/${TERRAFORM_VERSION}/terraform_${TERRAFORM_VERSION}_linux_amd64.zip && unzip terraform_${TERRAFORM_VERSION}_linux_amd64.zip -d /usr/local/bin/ RUN set -ex \ && mkdir -p $HOME/.terraform.d/plugin-cache && echo 'plugin_cache_dir = "$HOME/.terraform.d/plugin-cache"' > ~/.terraformrc #************************* Terragrunt ************************************* ARG TERRAGRUNT_VERSION=0.55.1 RUN set -ex \ && wget https://github.com/gruntwork-io/terragrunt/releases/download/v${TERRAGRUNT_VERSION}/terragrunt_linux_amd64 -q \ && mv terragrunt_linux_amd64 /usr/local/bin/terragrunt \ && chmod +x /usr/local/bin/terragrunt #*********************** Terramate **************************************** ARG TERRAMATE_VERSION=0.4.5 RUN set -ex \ && wget https://github.com/mineiros-io/terramate/releases/download/v${TERRAMATE_VERSION}/terramate_${TERRAMATE_VERSION}_linux_x86_64.tar.gz \ && tar -xzf terramate_${TERRAMATE_VERSION}_linux_x86_64.tar.gz \ && mv terramate /usr/local/bin/terramate \ && chmod +x /usr/local/bin/terramate #*********************** tfsec ******************************************** ARG TFSEC_VERSION=1.28.5 RUN set -ex \ && wget https://github.com/aquasecurity/tfsec/releases/download/v${TFSEC_VERSION}/tfsec-linux-amd64 \ && mv tfsec-linux-amd64 /usr/local/bin/tfsec \ && chmod +x /usr/local/bin/tfsec \ && terragrunt --version #**********************Terraform docs ************************************ ARG TERRRAFORM_DOCS_VERSION=0.17.0 RUN set -ex \ && curl -sSLo ./terraform-docs.tar.gz https://terraform-docs.io/dl/v${TERRRAFORM_DOCS_VERSION}/terraform-docs-v${TERRRAFORM_DOCS_VERSION}-$(uname)-amd64.tar.gz \ && tar -xzf terraform-docs.tar.gz \ && chmod +x terraform-docs \ && mv terraform-docs /usr/local/bin/terraform-docs #********************* ShellCheck ***************************************** ARG SHELLCHECK_VERSION="stable" RUN set -ex \ && wget -qO- "https://github.com/koalaman/shellcheck/releases/download/${SHELLCHECK_VERSION?}/shellcheck-${SHELLCHECK_VERSION?}.linux.x86_64.tar.xz" | tar -xJv \ && cp "shellcheck-${SHELLCHECK_VERSION}/shellcheck" /usr/bin/ \ && shellcheck --version ...

ShellCheck: https://github.com/koalaman/shellcheck

If I want to write better shell scripts I usually run shellcheck and adjust accordingly or if I need facilities not provided by the shell i switch to a full fledged programming language. Ans oh yes, `sh` is present almost on every BSD and Linux box for free so I consider it an important thing to at least be comfortable with.

shellcheck: https://www.shellcheck.net/

When I run nix-shell at the root of the project it puts me in a Nix shell that contains, among other programs, caddy and shellcheck. Notice that in the shellHook I add the project's shell scripts to the PATH. So once I'm in the Nix shell I can, among other things:

I have also seen some projects on github like ShellCheck which first make a library, expose all the modules and then simple add that do build-depends of the final executable. Is this the recommended approach than having just one executable and adding all the modules to other-modules:?

The error checks can be pretty arcane:

   https://github.com/koalaman/shellcheck/wiki/Checks

Similar to for instance shellcheck to check the syntax of shell scripts, is there an equivalent for the set of roff commands typically used in a (Linux) man page? I'm aware that e.g. pandoc permits the conversion of an other format (e.g., org) to both roff man and roff ms.