replace \ with function

[jsocolar]

Submission Checklist

• Run unit tests
• Declare copyright holder and agree to license (see below)

Summary

This enables cmdstanr to install on R versions <= 4.0. I've tested on 4.0, but not explicitly on earlier versions. Can close #788

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[rok-cesnovar]

Thanks a ton! Will merge when/if the tests pass.

[codecov-commenter]

Codecov Report

Merging #789 (aa1545e) into master (dbf41cd) will decrease coverage by 0.01%.
The diff coverage is 100.00%.

❗ Current head aa1545e differs from pull request most recent head 2a002e5. Consider uploading reports for the commit 2a002e5 to get more accurate results

@@            Coverage Diff             @@
##           master     #789      +/-   ##
==========================================
- Coverage   88.24%   88.24%   -0.01%     
==========================================
  Files          12       12              
  Lines        4152     4151       -1     
==========================================
- Hits         3664     3663       -1     
  Misses        488      488              

Impacted Files	Coverage Δ
R/fit.R	96.21% <100.00%> (-0.01%)	⬇️

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[jsocolar]

Looks like this is finally passing on R 3.6. Couple of things:

• CI won't pass on R 3.5 because RcppEigen apparently depends >= 3.6. Since RcppEigen is just in suggests, maybe no change is necessary, but wanted to flag in case it's cleaner to bump the depends to R 3.6. I don't know what changed between 3.5 and 3.6, but it seems like there's always a risk of introducing patterns that break in 3.5 when we can't test 3.5 on CI.
• R added the simplify argument to apply in 4.1. I've coded around that in 2a002e5. However, I haven't actually stepped through that function and looked at the behavior of the workaround; I'm just trusting the test harness to catch problems. Just want to flag for you that you might want to double check that change.

[rok-cesnovar]

We can leave it at 3.5 for now, given that rcppeigen is not mandatory. The apply change looks fine to me, thanks for highlighting it!

[jgabry]

Thanks Jacob and Rok!

…

On Thu, Jul 20, 2023 at 4:49 AM Rok Češnovar ***@***.***> wrote: Merged #789 <#789> into master. — Reply to this email directly, view it on GitHub <#789 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AB3PQQZXYE6ZRNYEQIGPAPTXREEMLANCNFSM6AAAAAA2QH53AM> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>