From ad835e095a806c0504dd1ca53611f08c21687876 Mon Sep 17 00:00:00 2001
From: Michael Bleuez <michael.bleuez2@gmail.com>
Date: Sun, 6 Feb 2022 16:16:43 +0100
Subject: [PATCH] F# support

---
 CHANGELOG.md           |  3 +++
 README.md              |  1 +
 doc/FSharp_Original.md | 60 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 64 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index d1f29fa6..99d00b05 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,6 @@
+## v1.2.1
+- F# support
+
 ## v1.2
 - Live mode (a @ChristianChiarulli idea and partial realisation)
 - Lower ressources usage for REPL interpreters
diff --git a/README.md b/README.md
index 3028da05..ce1a8eb7 100755
--- a/README.md
+++ b/README.md
@@ -431,6 +431,7 @@ println!("-> {}", alphabet);
 | C++          | Import        |  No              | 
 | Coffeescript | Bloc          |  No              |   
 | D            | Bloc          |  No              | 
+| F#           | Bloc          |  No, but _could_ \*\* |
 | Go           | Bloc          |  No              | 
 | Haskell      | Line          |  No              | 
 | Java       | Bloc             | No              | 
diff --git a/doc/FSharp_Original.md b/doc/FSharp_Original.md
index 4bdc7d06..37592088 100644
--- a/doc/FSharp_Original.md
+++ b/doc/FSharp_Original.md
@@ -1 +1,61 @@
 # This interpreter relies on dotnet fsi being available and on your path
+
+
+The default interpreter command is `dotnet fsi --nologo` but it can be changed via the configuration key
+
+
+```
+require'sniprun'.setup({
+    interpreter_options = {
+        FSharp_fifo = {
+             interpreter = "...."
+            }
+        }
+    }
+})
+```
+
+
+### REPL (would solve slowness issues)
+
+For now, REPL is broken due to dotnet fsi being capricious about its stdin.
+
+I'll explain rapidly how sniprun implement a REPL interpreter around named pipes (FIFOs).
+
+The first time a fifo-based interpreter receive a run command, it forks to the background and executes `ressources/init_repl.sh`.
+There is a lot of thing in that script but to replicate, you just have to:
+
+
+
+- `mkfifo pipe_in`
+
+- create a launcher script:
+
+```bash
+#!/bin/bash
+/bin/cat pipe_in | dotnet fsi 
+
+# or replace 'dotnet fsi' by whatever you cant to try
+```
+
+- launch it in the background: `bash ./launcher.sh &`, (or `bash ./launcher.sh > out.txt & ` to redirect stdout to out.txt like sniprun does)
+
+- ensure the pipe will stay open: `sleep 3600 > pipe_in &` (cat, exec 3> variations will also work)
+
+- `echo "printfn \" hey \" " > pipe_in` or `cat hello_world.fsx > pipe_in`
+
+- normally, the result should be printed in the terminal that ran the launcher, or in the out file.
+
+
+
+
+#### The issue:
+
+right now, dotnet fsi looks like it's blocked by the first sleep > pipe_in... but something **has** to keep the pipe open or when it closes, the fsi REPL reading from that will exit.
+
+I suspect the thing has something to do with interactive mode. 
+
+For example, `python` has a similar problem, but `python -i ` (forced interactive mode, even if no terminal is detected because it runs in the background / its stdin was hijacked) works fine in the above example.
+
+If you find something to replace dotnet fsi with, that exhibits the same correct behavior as `python -i`, sniprun REPL mode _should_ work.
+