mighty

commit 64c941a864332e2fa9813345b8885636ff124b5f
parent f27e8eb9a680a1d1d70e3ef0e95fa91662d374fa
Author: citbl <citbl@citbl.org>
Date:   Tue, 26 May 2026 20:48:40 +1000

parser wip

Diffstat:
M
mtcl/ast.lua
 | 
14
++++++++++++++
M
mtcl/parser.lua
 | 
98
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-------------

2 files changed, 96 insertions(+), 16 deletions(-)
diff --git a/mtcl/ast.lua b/mtcl/ast.lua
@@ -14,6 +14,20 @@ function AST:use(lib)
 	}
 end
 
+function AST:binary(op, lhs, rhs)
+	return {
+		op = op,
+		lhs = lhs,
+		rhs = rhs,
+	}
+end
+
+-- note the name/callee etc. usually carries the token so we have file/line/col
+-- access via lexeme
+function AST:call(callee, args)
+	return { callee = callee, args = args }
+end
+
 function AST:func(name, params, ret, body)
 	return {
 		kind = "func",
diff --git a/mtcl/parser.lua b/mtcl/parser.lua
@@ -1,6 +1,5 @@
 local parser = { pos = 1, nodes = {} }
 local ast = require("ast")
-local node = {}
 
 function parser:peek()
 	return self.tokens[self.pos] or 0
@@ -36,32 +35,98 @@ function parser:add(ast)
 	self.nodes[#self.nodes + 1] = ast
 end
 
-function parser:parse_var() print("todo parse_var") end
-function parser:parse_while() print("todo parse_while") end
-function parser:parse_for() print("todo parse_for") end
-function parser:parse_return() print("todo parse_return") end
-function parser:parse_as_cast() print("todo parse_as_cast") end
-function parser:parse_call() print("todo parse_call") end
+function parser:parse_relational() end
+
+function parser:parse_equality()
+	local node = parser:parse_relational()
+
+	while true do
+		if parser:peek().kind == TK.EQEQ then
+			local rhs = parser:parse_relational()
+			node = ast.binary(OP.EQUALITY, node, rhs)
+		-- elseif next == TK.BANGEQ then
+		-- todo inequality
+		else
+			break
+		end
+	end
+	return node
+end
+
+function parser:parse_assignment_expr()
+	local left = parser:parse_equality()
+
+	if parser:peek().kind == TK.EQ then
+		local right = parser:parse_assignment_expr()
+		-- todo check fail assignment target
+		-- todo make binary node
+	end
+
+	return left
+end
+
+function parser:parse_expr()
+	return parser:parse_assignment_expr()
+end
+
+function parser:parse_var()
+	print("todo parse_var")
+end
+function parser:parse_while()
+	print("todo parse_while")
+end
+function parser:parse_for()
+	print("todo parse_for")
+end
+function parser:parse_return()
+	print("todo parse_return")
+end
+function parser:parse_as_cast()
+	print("todo parse_as_cast")
+end
+function parser:parse_call()
+	-- parse ident, parse parameters
+	local callee = parser:expect(TK.IDENT)
+	print("parse_call")
+	parser:expect(TK.L_PAREN) -- swallow (
+	local args = {}
+	while parser:peek().kind ~= TK.R_PAREN do -- call parameters
+		local expr = parser:parse_expr()
+		args[#args + 1] = expr
+		if parser:peek().kind == TK.COMMA then
+			parser:advance()
+		else
+			break
+		end
+	end
+	return ast.call(callee, args)
+end
 
 function parser:parse_statement()
 	local first = parser:peek().kind
 	local second = parser:nextpeek().kind
-	print("todo parse statement: " .. first)
 	if first == TK.IDENT then
 		if second == TK.L_PAREN then
-			parser:parse_call()
+			return parser:parse_call()
 		elseif second == TK.IDENT then
-			parser:parse_var()
+			return parser:parse_var()
+		else
+			print("parse_statement unhandled ident start with: " .. second)
 		end
 	elseif first == TK.KEYWORD then
 		local kw = parser:peek()
-		if kw.lexeme == "while" then parse:parse_while() 
-		elseif kw.lexeme == "for" then parse:parse_for()
-		elseif kw.lexeme == "return" then parse:parse_return()
-		elseif kw.lexeme == "as" then parse:parse_as_cast()
+		if kw.lexeme == "while" then
+			return parser:parse_while()
+		elseif kw.lexeme == "for" then
+			return parser:parse_for()
+		elseif kw.lexeme == "return" then
+			return parser:parse_return()
+		elseif kw.lexeme == "as" then
+			return parser:parse_as_cast()
+		else
+			print("parse_statement unhandled keyword yet: " .. kw.lexeme)
 		end
 	end
-	parser:advance()
 end
 
 function parser:parse_function(is_exported)
@@ -99,8 +164,9 @@ function parser:parse_function(is_exported)
 		-- function body statements
 		local stmt = parser:parse_statement()
 		statements[#statements + 1] = stmt
+		parser:advance()
 	end
-	local node = ast.func(name, params, ret, statements)
+	local node = ast.func(name, parameters, ret, statements)
 	parser:add(node)
 end