# Best practice calling racket from rash?

**URL:** <https://racket.discourse.group/t/best-practice-calling-racket-from-rash/3346>\
**Category:** General\
**Created:** [November 21, 2024, 11:09pm UTC](https://racket.discourse.group/t/best-practice-calling-racket-from-rash/3346 "2024-11-21T23:09:52Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![jbclements](https://yyz2.discourse-cdn.com/free1/user_avatar/racket.discourse.group/jbclements/32/11_2.png) [@jbclements](https://racket.discourse.group/u/jbclements)\
**Post date:** [November 21, 2024, 11:09pm UTC](https://racket.discourse.group/t/best-practice-calling-racket-from-rash/3346/1 "2024-11-21T23:09:52Z")

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I'm starting to use rash, and having a lot of fun. One question that I have is around best practices when invoking racket code. Specifically, as you might imagine, I have a bunch of shell scripts that invoke racket. When using Rash, I have the ability to make these "internal"; that is, my shell is in fact Racket, so I can just call this code directly. This makes me a bit nervous, in that I somehow feel as though the operating system's process abstraction is going to protect my shell-running racket even when my invoked-process racket goes belly-up... but maybe that's not really a problem in practice.

Does anyone have experience they can share?

Here's a simple blob of rash code formatted as a rashrc.rkt, replacing a `ccs` shell script that connects these two invocations of racket with `&&`, to show what I mean (and also to invite criticism; I suspect that I'm making a lot of simple things harder...)

```scheme
#lang rash

(require shell/pipeline-macro
         (for-syntax racket syntax/parse))

(provide ccs)

(define (check-schedule)
        {raco make -v $HOME/scheduling/check-schedule.rkt}
        {racket $HOME/scheduling/check-schedule.rkt})

(define-pipeline-alias ccs
  (syntax-parser
    [(_) #'(=basic-object-pipe/form= check-schedule)]))

```

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<div class="post-metadata">

**Author:** ![ixemad](https://yyz2.discourse-cdn.com/free1/user_avatar/racket.discourse.group/ixemad/32/2075_2.png) [@ixemad](https://racket.discourse.group/u/ixemad)\
**Post date:** [December 5, 2024, 9:15am UTC](https://racket.discourse.group/t/best-practice-calling-racket-from-rash/3346/2 "2024-12-05T09:15:14Z")

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Even though I love Racket, I can only use it from time to time. Back in the time, I saw Rash as a good oportunity to use Racket in my daily tasks.

I probably can't answer your question, but perhaps you can think of your Rash code not as isolated scripts, but rather as modules that you can reuse.

Finally, I fully understand you about having a lot of fun with the Racket / Rash pairing 🥲:

```scheme
(require racket/function
         racket/string
         racket/stream
         json
         qi )

(define (/ entry-name)
  (☯ (~> (hash-ref entry-name) (if list? sep _))))

(define (@ entry-name op entry-value)
  (☯ (pass (esc (λ (key) (op (hash-ref key entry-name) entry-value))))) )

(void (putenv "AWS_ACCESS_KEY_ID" #{ echo $assumed-role | jq -r ".Credentials.AccessKeyId" }))
(void (putenv "AWS_SECRET_ACCESS_KEY" #{ echo $assumed-role | jq -r ".Credentials.SecretAccessKey" }))
(void (putenv "AWS_SESSION_TOKEN" #{ echo $assumed-role | jq -r ".Credentials.SessionToken" }))

(let ([lambdas
       (for*/stream ([region (string-split regions)]
                     [result (in-list
                              (with-handlers ([exn:fail? (const '())])
                                #{ aws lambda list-functions \
                                       --region $region \
                                       |>> string->jsexpr \
                                       |> (☯ (~> (/ 'Functions)
                                                 (>< (/ 'FunctionArn))
                                                 ▽)) } ) ) ] )
         result) ])
  (if (stream-empty? lambdas)
      "no lambdas in any region"
      (~> (lambdas) stream-first display) ) )

```

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<div class="post-metadata">

**Author:** ![benknoble](https://yyz2.discourse-cdn.com/free1/user_avatar/racket.discourse.group/benknoble/32/16_2.png) [@benknoble](https://racket.discourse.group/u/benknoble)\
**Post date:** [December 5, 2024, 3:53pm UTC](https://racket.discourse.group/t/best-practice-calling-racket-from-rash/3346/3 "2024-12-05T15:53:15Z")

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Be careful with `echo` due to escape strings and special meanings; `printf '%s\n'` is more portable and won’t do strange things to its input.