From 67c952bc21473474ee82383e75c6a42f077c0c49 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=89tienne=20Reuh=20Fildadut?= <fildadut@reuh.eu>
Date: Sun, 7 Jan 2024 18:22:55 +0100
Subject: [PATCH] Allow adding overload to overload

---
 anselme/ast/Definition.lua  |  6 +++---
 anselme/ast/Environment.lua |  2 +-
 anselme/ast/Overload.lua    | 14 ++++++++++----
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/anselme/ast/Definition.lua b/anselme/ast/Definition.lua
index 593d420..626457f 100644
--- a/anselme/ast/Definition.lua
+++ b/anselme/ast/Definition.lua
@@ -1,5 +1,5 @@
 local ast = require("anselme.ast")
-local Nil, Overloadable
+local Nil, Overloadable, Overload
 
 local operator_priority = require("anselme.common").operator_priority
 
@@ -30,7 +30,7 @@ local Definition = ast.abstract.Node {
 		local symbol = self.symbol:eval(state)
 		local val = self.expression:eval(state)
 
-		if Overloadable:issub(val) then
+		if Overloadable:issub(val) or Overload:is(val) then
 			state.scope:define_overloadable(symbol, val)
 		else
 			state.scope:define(symbol, val)
@@ -41,6 +41,6 @@ local Definition = ast.abstract.Node {
 }
 
 package.loaded[...] = Definition
-Nil, Overloadable = ast.Nil, ast.abstract.Overloadable
+Nil, Overloadable, Overload = ast.Nil, ast.abstract.Overloadable, ast.Overload
 
 return Definition
diff --git a/anselme/ast/Environment.lua b/anselme/ast/Environment.lua
index 1a2b31f..27c3f65 100644
--- a/anselme/ast/Environment.lua
+++ b/anselme/ast/Environment.lua
@@ -123,7 +123,7 @@ local Environment = ast.abstract.Runtime {
 	end,
 	-- define or redefine new overloadable variable in current environment, inheriting existing overload variants from (parent) scopes
 	define_overloadable = function(self, state, symbol, exp)
-		assert(Overloadable:issub(exp), "trying to add an non-overloadable value to an overload")
+		assert(Overloadable:issub(exp) or Overload:is(exp), "trying to add an non-overloadable value to an overload")
 
 		local identifier = symbol:to_identifier()
 
diff --git a/anselme/ast/Overload.lua b/anselme/ast/Overload.lua
index 400cd50..41721b6 100644
--- a/anselme/ast/Overload.lua
+++ b/anselme/ast/Overload.lua
@@ -17,9 +17,15 @@ Overload = ast.abstract.Node {
 		end
 	end,
 	insert = function(self, val) -- only for construction
-		assert0(not self._signatures[val:hash_signature()], ("a function with parameters %s is already defined in the overload"):format(val:format_signature()))
-		table.insert(self.list, val)
-		self._signatures[val:hash_signature()] = true
+		if Overload:is(val) then
+			for _, overloadable in ipairs(val.list) do
+				self:insert(overloadable)
+			end
+		else
+			assert0(not self._signatures[val:hash_signature()], ("a function with parameters %s is already defined in the overload"):format(val:format_signature()))
+			table.insert(self.list, val)
+			self._signatures[val:hash_signature()] = true
+		end
 	end,
 
 	_format = function(self, ...)
@@ -61,7 +67,7 @@ Overload = ast.abstract.Node {
 		if success then
 			return success, args
 		else
-			return nil, ("no function match arguments %s, possible functions were:\n\t• %s"):format(args:format(state), table.concat(failure, "\n\t• "))
+			return nil, ("no function match arguments %s, possible functions were:\n\t• %s"):format(args:format_short(state), table.concat(failure, "\n\t• "))
 		end
 	end
 }