R Packages Not Available via Nix?

[idontgetoutmuch]

I have

let

rOverlay = rself: rsuper: {
  myR = rsuper.rWrapper.override {
    packages = with rsuper.rPackages; [
      ggplot2
      dplyr
      xts
      purrr
    ];
  };
};

haskellOverlay = hself: hsuper: {
  my-inline-r = hself.haskell.lib.dontCheck (hsuper.haskellPackages.inline-r);
};

in

let
  pkgs = import <nixpkgs> { overlays = [ rOverlay haskellOverlay ]; };

  h = pkgs.haskellPackages.extend (self: super: {
    nz-inline-r = pkgs.haskell.lib.dontCheck super.inline-r;
});

in

  pkgs.mkShell {
    buildInputs = [
      pkgs.myR
      (h.ghcWithPackages (p: [ (p.nz-inline-r) ]))
    ];
  }

nix-shell bar.nix -I nixpkgs=https://github.com/NixOS/nixpkgs-channels/archive/nixos-19.03.tar.gz
[nix-shell:~/nix2]$ ghci -fno-ghci-sandbox
GHCi, version 8.6.4: http://www.haskell.org/ghc/  :? for help
Prelude> :set -XQuasiQuotes
Prelude> :set -XTemplateHaskell
Prelude> import qualified Language.R as R
Prelude R> import Language.R.QQ
Prelude R Language.R.QQ>   R.runRegion $ do _ <- [r| print(pi) |]; return ()
[1] 3.141593
Prelude R Language.R.QQ>   R.runRegion $ do x <- [r| loadedNamespaces() |]; [r| print(x_hs) |]; return ()
[1] "compiler"  "graphics"  "utils"     "grDevices" "stats"     "datasets" 
[7] "methods"   "base"     
Prelude R Language.R.QQ>   R.runRegion $ do x <- [r| library(dplyr) |]; [r| print(x_hs) |]; return ()
*** Exception: R Runtime Error: Error in library(dplyr) : there is no package called ‘dplyr’

Prelude R Language.R.QQ> import System.Process
Prelude R Language.R.QQ System.Process> r <- createProcess (proc "which" ["R"])
Prelude R Language.R.QQ System.Process> /nix/store/rs8l60kcfbz2jbq5g4b75n82jvlpjydm-R-3.5.2-wrapper/bin/R

OTOH

[nix-shell:~/nix2]$ R

R version 3.5.2 (2018-12-20) -- "Eggshell Igloo"
Copyright (C) 2018 The R Foundation for Statistical Computing
Platform: x86_64-apple-darwin17.7.0 (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

  Natural language support but running in an English locale

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> loadedNamespaces()
[1] "compiler"  "graphics"  "utils"     "grDevices" "stats"     "datasets" 
[7] "methods"   "base"     
> library(dplyr)

Attaching package: ‘dplyr’

The following objects are masked from ‘package:stats’:

    filter, lag

The following objects are masked from ‘package:base’:

    intersect, setdiff, setequal, union

and

[nix-shell:~/nix2]$ which R
/nix/store/rs8l60kcfbz2jbq5g4b75n82jvlpjydm-R-3.5.2-wrapper/bin/R

[idontgetoutmuch]

This seems to work

{ nixpkgs ? import <nixpkgs> {} }:

let

  haskellDeps = ps: with ps; [
    (nixpkgs.haskell.lib.dontCheck inline-r)
  ];

in

  nixpkgs.stdenv.mkDerivation {
  name = "env";
  buildInputs = [
    (nixpkgs.haskellPackages.ghcWithPackages haskellDeps)
    nixpkgs.R
    nixpkgs.rPackages.dplyr
  ];
}