3 files changed, 132 insertions, 10 deletions
diff --git a/users/Profpatsch/lib.nix b/users/Profpatsch/lib.nix
index 69e6f73e408a..9215f5b19c77 100644
--- a/users/Profpatsch/lib.nix
+++ b/users/Profpatsch/lib.nix
@@ -1,6 +1,8 @@
 { depot, pkgs, ... }:
 let
-  bins = depot.nix.getBins pkgs.coreutils ["printf" "echo"];
+  bins = depot.nix.getBins pkgs.coreutils [ "printf" "echo" "cat" "printenv" ]
+      // depot.nix.getBins pkgs.fdtools [ "multitee" ]
+      ;
 
   debugExec = msg: depot.nix.writeExecline "debug-exec" {} [
     "if" [
@@ -15,9 +17,19 @@ let
     "fdmove" "-c" "1" "2" bins.printf "$@"
   ];
 
+  eprint-stdin = depot.nix.writeExecline "eprint-stdin" {} [
+    "pipeline" [ bins.multitee "0-1,2" ] "$@"
+  ];
+
+  eprintenv = depot.nix.writeExecline "eprintenv" { readNArgs = 1; } [
+    "fdmove" "-c" "1" "2" bins.printenv "$1"
+  ];
+
 in {
   inherit
     debugExec
     eprintf
+    eprint-stdin
+    eprintenv
     ;
 }
diff --git a/users/Profpatsch/rust-crates.nix b/users/Profpatsch/rust-crates.nix
index ebe6d73ceba9..ecf3c960775b 100644
--- a/users/Profpatsch/rust-crates.nix
+++ b/users/Profpatsch/rust-crates.nix
@@ -50,4 +50,36 @@ rec {
     buildDependencies = [ cc ];
     sha256 = "0jwwbvs4icpra7m1ycvnyri5h3sbw4qrfvgnnvnk72h4w93qhzhr";
   };
+
+  libc = pkgs.buildRustCrate {
+    pname = "libc";
+    crateName = "libc";
+    version = "0.2.82";
+    sha256 = "02zgn6c0xwh331hky417lbr29kmvrw3ylxs8822syyhjfjqszvsx";
+  };
+
+  bitflags = pkgs.buildRustCrate {
+    pname = "bitflags";
+    crateName = "bitflags";
+    version = "1.2.1";
+    sha256 = "0b77awhpn7yaqjjibm69ginfn996azx5vkzfjj39g3wbsqs7mkxg";
+  };
+
+  inotify-sys = pkgs.buildRustCrate {
+    pname = "inotify-sys";
+    crateName = "inotify-sys";
+    version = "0.1.5";
+    dependencies = [ libc ];
+    sha256 = "1yiy577xxhi0j90nbg9nkd8cqwc1xix62rz55jjngvxa5jl5613v";
+  };
+
+  inotify = pkgs.buildRustCrate {
+    pname = "inotify";
+    crateName = "inotify";
+    version = "0.9.2";
+    edition = "2018";
+    dependencies = [ bitflags libc inotify-sys ];
+    sha256 = "0fcknyvknglwwk1pdzdlb4m0ry2dym1yx8r5prf2v00pxnjk0hv2";
+  };
+
 }
diff --git a/users/Profpatsch/tree-sitter.nix b/users/Profpatsch/tree-sitter.nix
index dd1dc05a6401..4a05c825bab4 100644
--- a/users/Profpatsch/tree-sitter.nix
+++ b/users/Profpatsch/tree-sitter.nix
@@ -1,15 +1,17 @@
 { depot, pkgs, lib, ... }:
 
 let
+  bins = depot.nix.getBins pkgs.coreutils [ "head" "printf" "cat" ]
+      // depot.nix.getBins pkgs.ncurses [ "tput" ]
+      // depot.nix.getBins pkgs.bc [ "bc" ]
+      // depot.nix.getBins pkgs.ocamlPackages.sexp [ "sexp" ];
+
   print-ast = depot.users.Profpatsch.writers.rustSimple {
     name = "print-ast";
     dependencies = with depot.users.Profpatsch.rust-crates; [
       libloading
       tree-sitter
     ];
-    buildInputs = [
-      pkgs.tree-sitter
-    ];
   } ''
     extern crate libloading;
     extern crate tree_sitter;
@@ -39,9 +41,7 @@ let
       let mut parser = Parser::new();
       let lang = _load_language(so, symbol_name).unwrap();
       parser.set_language(lang).unwrap();
-      let mut bytes = Vec::new();
-      let mut file = std::fs::OpenOptions::new().read(true).open(file).unwrap();
-      file.read_to_end(&mut bytes);
+      let bytes = std::fs::read(&file).unwrap();
       print!("{}", parser.parse(&bytes, None).unwrap().root_node().to_sexp());
     }
 
@@ -58,8 +58,85 @@ let
     };
   };
 
-  parse-nix-file = depot.nix.writeExecline "parse-nix-file" { readNArgs = 1; } [
-    print-ast "${tree-sitter-nix}/parser" "tree_sitter_nix" "$1"
+  watch-file-modified = depot.users.Profpatsch.writers.rustSimple {
+    name = "watch-file-modified";
+    dependencies = [ depot.users.Profpatsch.rust-crates.inotify ];
+  } ''
+    extern crate inotify;
+    use inotify::{EventMask, WatchMask, Inotify};
+    use std::io::Write;
+
+    fn main() {
+        let mut inotify = Inotify::init()
+            .expect("Failed to initialize inotify");
+
+        let file = std::env::args().nth(1).unwrap();
+
+        let file_watch = inotify
+            .add_watch(
+                &file,
+                WatchMask::MODIFY
+            )
+            .expect("Failed to add inotify watch");
+
+        fn to_netstring(s: &[u8]) -> Vec<u8> {
+            let len = s.len();
+            // length of the integer as ascii
+            let i_len = ((len as f64).log10() as usize) + 1;
+            let ns_len = i_len + 1 + len + 1;
+            let mut res = Vec::with_capacity(ns_len);
+            res.extend_from_slice(format!("{}:", len).as_bytes());
+            res.extend_from_slice(s);
+            res.push(b',');
+            res
+        }
+
+        let mut buffer = [0u8; 4096];
+        loop {
+            let events = inotify
+                .read_events_blocking(&mut buffer)
+                .expect("Failed to read inotify events");
+
+            for event in events {
+                if event.wd == file_watch {
+                  std::io::stdout().write(&to_netstring(file.as_bytes()));
+                  std::io::stdout().flush();
+                }
+            }
+        }
+    }
+
+  '';
+
+  # clear screen and set LINES and COLUMNS to terminal height & width
+  clear-screen = depot.nix.writeExecline "clear-screen" {} [
+    "if" [ bins.tput "clear" ]
+    "backtick" "-in" "LINES" [ bins.tput "lines" ]
+    "backtick" "-in" "COLUMNS" [ bins.tput "cols" ]
+    "$@"
+  ];
+
+  print-nix-file = depot.nix.writeExecline "print-nix-file" { readNArgs = 1; } [
+    "pipeline" [ print-ast "${tree-sitter-nix}/parser" "tree_sitter_nix" "$1" ]
+    "pipeline" [ bins.sexp "print" ]
+    clear-screen
+    "importas" "-ui" "lines" "LINES"
+    "backtick" "-in" "ls" [
+      "pipeline"
+        # when you pull out bc to decrement an integer it’s time to switch to python lol
+        [ bins.printf "x=%s; --x\n" "$lines" ]
+        bins.bc
+    ]
+    "importas" "-ui" "l" "ls"
+    bins.head "-n\${l}"
+  ];
+
+  print-nix-file-on-update = depot.nix.writeExecline "print-nix-file-on-update" { readNArgs = 1; } [
+    "if" [ print-nix-file "$1" ]
+    "pipeline" [ watch-file-modified "$1" ]
+    "forstdin" "-d" "" "file"
+    "importas" "file" "file"
+    print-nix-file "$file"
   ];
 
   # copied from nixpkgs
@@ -104,6 +181,7 @@ in {
   inherit
     print-ast
     tree-sitter-nix
-    parse-nix-file
+    print-nix-file-on-update
+    watch-file-modified
     ;
 }