From 4eaaedc486d60fde724abf1af70e21fc2b3e5c49 Mon Sep 17 00:00:00 2001
From: Case Duckworth
Date: Sun, 31 Mar 2024 22:16:37 -0500
Subject: Add rest of quotes to reader

---
 read.lua | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/read.lua b/read.lua
index a41816f..f8d6b09 100644
--- a/read.lua
+++ b/read.lua
@@ -7,6 +7,12 @@ local pop = require("util").pop
 
 local pp = require("pp").pp
 
+-- TODO:
+-- - string reading
+-- - # syntax
+-- - comments
+-- - probably more
+
 function m.inport (source, kind)
 	-- KIND can be one of "file", "string"; defaults to "file"
 	-- SOURCE is the name of the file or the string to read, or nil; if nil,
@@ -85,6 +91,18 @@ end
 m.readtable = {
 	["("] = function (cs) return pop(cs), "open", cs end,
 	[")"] = function (cs) return pop(cs), "close", cs end,
+	["'"] = function (cs) return pop(cs), "quote", cs end,
+	["`"] = function (cs) return pop(cs), "quote", cs end,
+	[","] =
+		function (cs)
+			pop(cs) -- remove ','
+			if cs[1] == "@" then
+				pop(cs) -- remove '@'
+				return ",@", "quote", cs
+			else
+				return ",", "quote", cs
+			end
+		end,
 }
 
 -- Return an iterator over a character table, so you can do:
@@ -131,6 +149,24 @@ function m.readchar (port)
 	end
 end
 
+m.readmacros = {
+	quote =
+		function (tok, toktype, port)
+			local qs = {
+				["'"] = "quote",
+				["`"] = "quasiquote",
+				[","] = "unquote",
+				[",@"] = "unquote-splicing",
+			}
+			if not qs[tok] then
+				error(string.format("Bad quote: '%s'\n", tok))
+			end
+			local Q = {qs[tok]}
+			table.insert(Q, m.read(port))
+			return t.list(Q)
+		end,
+}
+
 function m.read (port)
 	local function read_ahead (tok, toktype)
 		if not tok then error("Unexpected EOF") end
@@ -151,6 +187,8 @@ function m.read (port)
 			end
 		elseif toktype == "close" then
 			error("Unexpected ')'")
+		elseif m.readmacros[toktype] then
+			return m.readmacros[toktype](tok, toktype, port)
 		else return tok
 		end
 	end
-- 
cgit 1.4.1-21-gabe81