From dd418aa196228735a350c507cc886c65ec1a6c1b Mon Sep 17 00:00:00 2001
From: Ram Krishnan <kriyative@gmail.com>
Date: Sat, 10 Nov 2018 19:50:10 -0800
Subject: [PATCH] Adds support for entering multi-line sexprs in REPL

---
 lib/stdio.fnl | 38 +++++++++++++++++++++++++++++++-------
 lib/stdio.lua | 51 ++++++++++++++++++++++++++++++++++++++++-----------
 2 files changed, 71 insertions(+), 18 deletions(-)

diff --git a/lib/stdio.fnl b/lib/stdio.fnl
index ebccbca..3d2bb67 100644
--- a/lib/stdio.fnl
+++ b/lib/stdio.fnl
@@ -1,4 +1,5 @@
 (require "love.event")
+(local fennel (require "lib.fennel"))
 (local view (require "lib.fennelview"))
 
 ;; This module exists in order to expose stdio over a channel so that it
@@ -6,14 +7,37 @@
 
 (local (event channel) ...)
 
+(defn display [s]
+  (io.write s)
+  (io.flush))
+
+(defn prompt []
+  (display "\n>> "))
+
+(defn read-chunk []
+  (let [input (io.read)]
+    (when input
+      (.. input "\n"))))
+
+(var input "")
 (when channel
-  (let [prompt (fn [] (io.write "> ") (io.flush) (io.read "*l"))]
-    ((fn looper [input]
-       (when input
-         ;; This is consumed by love.handlers[event]
-         (love.event.push event input)
-         (print (: channel :demand))
-         (looper (prompt)))) (prompt))))
+  (let [(bytestream clearstream) (fennel.granulate read-chunk)
+        read (fennel.parser
+              (fn []
+                (let [c (or (bytestream) 10)]
+                  (set input (.. input (string.char c)))
+                  c)))]
+    (while true
+      (prompt)
+      (set input "")
+      (let [(ok ast) (read)]
+        (if (not ok)
+            (do
+              (display (.. "Error:" (view ast) "\n"))
+              (clearstream))
+            (do
+              (love.event.push event input)
+              (display (: channel :demand))))))))
 
 {:start (fn start-repl []
           (let [code (love.filesystem.read "stdio.fnl")
diff --git a/lib/stdio.lua b/lib/stdio.lua
index 4640809..633a6a0 100644
--- a/lib/stdio.lua
+++ b/lib/stdio.lua
@@ -1,22 +1,51 @@
 require("love.event")
+local fennel = require("lib.fennel")
 local view = require("lib.fennelview")
 local event, channel = ...
+local function display(s)
+  io.write(s)
+  return io.flush()
+end
+do local _ = display end
+local function prompt()
+  return display("\n>> ")
+end
+do local _ = prompt end
+local function read_chunk()
+  local input = io.read()
+  if input then
+    return (input .. "\n")
+  end
+end
+do local _ = read_chunk end
+local input = ""
 local function _0_(...)
   if channel then
+    local bytestream, clearstream = fennel.granulate(read_chunk)
     local function _0_()
-      io.write("> ")
-      io.flush()
-      return io.read("*l")
+      local c = (bytestream() or 10)
+      input = (input .. string.char(c))
+      return c
     end
-    local prompt = _0_
-    local function looper(input)
-      if input then
-        love.event.push(event, input)
-        print(channel:demand())
-        return looper(prompt())
+    local read = fennel.parser(_0_)
+    while true do
+      prompt()
+      input = ""
+      do
+        local ok, ast = read()
+        local function _1_(...)
+          if not ok then
+            display(("Error:" .. view(ast) .. "\n"))
+            return clearstream()
+          else
+            love.event.push(event, input)
+            return display(channel:demand())
+          end
+        end
+        _1_(...)
       end
     end
-    return looper(prompt())
+    return nil
   end
 end
 _0_(...)
@@ -47,4 +76,4 @@ local function start_repl()
   love.handlers.eval = _2_
   return nil
 end
-return ({start = start_repl})
+return {start = start_repl}