feat: Infer empty list/map item/key/value type

closes #86
buzz-language · Jan 13, 2025 · a6a039c · a6a039c
1 parent 72a1396
commit a6a039c
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Showing 21 changed files with 101 additions and 50 deletions.
diff --git a/examples/2048.buzz b/examples/2048.buzz
@@ -41,7 +41,7 @@ object Pair {
 }
 
 object Game {
-    board: [[int]] = [<[int]>],
+    board: [[int]] = [],
     size: int = 4,
     goal: int = 2048,
     score: int = 0,
@@ -54,7 +54,7 @@ object Game {
         };
 
         foreach (x in 0..game.size) {
-            game.board.append([<int>]);
+            game.board.append([]);
 
             foreach (_ in 0..game.size) {
                 game.board[x].append(0);
@@ -91,7 +91,7 @@ object Game {
 
     // Return list of free spots
     fun freeSpots() > [obj{ x: int, y: int }] {
-        var spots = [<obj{ x: int, y: int }>];
+        var spots: [obj{ x: int, y: int }] = [];
 
         foreach (x, row in this.board) {
             foreach (y, value in row) {
@@ -154,7 +154,7 @@ object Game {
     }
 
     fun iterate(axis: bool, direction: int) > [Pair] {
-        var result = [<Pair>];
+        var result: [Pair] = [];
 
         foreach (x in 0..this.size) {
             foreach (y in 0..this.size) {

diff --git a/examples/brownian-tree.buzz b/examples/brownian-tree.buzz
@@ -78,7 +78,7 @@ fun main(_: [str]) > void !> SDLError {
 
     var canvas: [[bool]] = [];
     foreach (i in 0..sizeX) {
-        canvas.append([<bool>]);
+        canvas.append([]);
 
         foreach (_ in 0..sizeY) {
             canvas[i].append(false);

diff --git a/examples/game-of-life.buzz b/examples/game-of-life.buzz
@@ -12,7 +12,7 @@ object World {
         var world = World{
             width ,
             height,
-            cells = [<bool>],
+            cells = [],
         };
 
         for (i: int = 0; i < width * height; i = i + 1) {
@@ -36,7 +36,7 @@ object World {
     }
 
     fun step() > void {
-        var cells = [<bool>];
+        var cells = [];
         for (y: int = 0; y < this.height; y = y + 1) {
             for (x: int = 0; x < this.width; x = x + 1) {
                 final coordinate = y * this.width + x;

diff --git a/examples/sqlite.buzz b/examples/sqlite.buzz
@@ -156,7 +156,7 @@ export object Statement {
         std\print("Executing query `{this.query}`");
         var code: ResultCode = ResultCode.Ok;
 
-        final rows = [<[Boxed]>];
+        final rows: [[Boxed]] = [];
         while (code != ResultCode.Done) {
             code = ResultCode(sqlite3_step(this.stmt)) ?? ResultCode.Error;
             if (code != ResultCode.Ok and code != ResultCode.Row and code != ResultCode.Done) {
@@ -171,7 +171,7 @@ export object Statement {
             }
 
             final columnCount = sqlite3_column_count(this.stmt);
-            var row = [<any>];
+            var row: [any] = [];
             for (i: int = 0; i < columnCount; i = i + 1) {
                 final columnType = Type(sqlite3_column_type(this.stmt, col: i)) ?? Type.Null;
 

diff --git a/examples/voronoi-diagram.buzz b/examples/voronoi-diagram.buzz
@@ -13,9 +13,9 @@ fun hypot(x: int, y: int) > int {
 }
 
 fun generateVoronoi(renderer: Renderer, width: int, height: int, numCells: int) > void !> SDLError {
-    var nx = [<int>];
-    var ny = [<int>];
-    var colors = [<Color>];
+    var nx: [int] = [];
+    var ny: [int] = [];
+    var colors: [Color] = [];
 
     foreach (_ in 0..numCells) {
         nx.append(std\random(min: 0, max: width));

diff --git a/src/Codegen.zig b/src/Codegen.zig
@@ -1091,7 +1091,7 @@ fn generateCall(self: *Self, node: Ast.Node.Index, breaks: ?*Breaks) Error!?*obj
     // First push on the stack arguments has they are parsed
     var needs_reorder = false;
     for (components.arguments, 0..) |argument, index| {
-        const argument_type_def = type_defs[argument.value].?;
+        var argument_type_def = type_defs[argument.value].?;
         const arg_key = if (argument.name) |arg_name|
             try self.gc.copyString(lexemes[arg_name])
         else
@@ -1109,6 +1109,9 @@ fn generateCall(self: *Self, node: Ast.Node.Index, breaks: ?*Breaks) Error!?*obj
 
         // Type check the argument
         if (def_arg_type) |arg_type| {
+            self.populateEmptyCollectionType(argument.value, arg_type);
+            argument_type_def = type_defs[argument.value].?;
+
             if (argument_type_def.def_type == .Placeholder) {
                 self.reporter.reportPlaceholder(self.ast, argument_type_def.resolved_type.?.Placeholder);
             } else if (!arg_type.eql(argument_type_def)) {
@@ -1513,7 +1516,7 @@ fn generateDot(self: *Self, node: Ast.Node.Index, breaks: ?*Breaks) Error!?*obj.
             switch (components.member_kind) {
                 .Value => {
                     const value = components.value_or_call_or_enum.Value;
-                    const value_type_def = type_defs[value].?;
+                    var value_type_def = type_defs[value].?;
                     if (value_type_def.def_type == .Placeholder) {
                         self.reporter.reportPlaceholder(self.ast, value_type_def.resolved_type.?.Placeholder);
                     }
@@ -1571,6 +1574,9 @@ fn generateDot(self: *Self, node: Ast.Node.Index, breaks: ?*Breaks) Error!?*obj.
                                 );
                             }
 
+                            self.populateEmptyCollectionType(value, field.?.type_def);
+                            value_type_def = type_defs[value].?;
+
                             if (!field.?.type_def.eql(value_type_def)) {
                                 self.reporter.reportTypeCheck(
                                     .assignment_value_type,
@@ -3011,7 +3017,9 @@ fn generateObjectDeclaration(self: *Self, node: Ast.Node.Index, breaks: ?*Breaks
                                 self.ast,
                                 type_defs[member.method_or_default_value.?].?.resolved_type.?.Placeholder,
                             );
-                        } else if (!mkv.value_ptr.*.type_def.eql(type_defs[member.method_or_default_value.?].?)) {
+                        } else if (!mkv.value_ptr.*.type_def.eql(type_defs[member.method_or_default_value.?].?) or
+                            mkv.value_ptr.*.mutable != object_def.fields.get(mkv.key_ptr.*).?.mutable)
+                        {
                             self.reporter.reportTypeCheck(
                                 .protocol_conforming,
                                 protocol_def.location,
@@ -3114,7 +3122,9 @@ fn generateObjectDeclaration(self: *Self, node: Ast.Node.Index, breaks: ?*Breaks
 
             // Create property default value
             if (member.method_or_default_value) |default| {
+                self.populateEmptyCollectionType(default, property_type);
                 const default_type_def = type_defs[default].?;
+
                 if (default_type_def.def_type == .Placeholder) {
                     self.reporter.reportPlaceholder(self.ast, default_type_def.resolved_type.?.Placeholder);
                 } else if (!property_type.eql(default_type_def)) {
@@ -3232,11 +3242,12 @@ fn generateObjectInit(self: *Self, node: Ast.Node.Index, breaks: ?*Breaks) Error
             node_type_def.resolved_type.?.ForeignContainer
                 .fields.getIndex(property_name);
 
-        const value_type_def = type_defs[property.value].?;
-
         if (fields.get(property_name)) |prop| {
             try self.OP_COPY(location, 0); // Will be popped by OP_SET_PROPERTY
 
+            self.populateEmptyCollectionType(property.value, prop);
+            const value_type_def = type_defs[property.value].?;
+
             if (value_type_def.def_type == .Placeholder) {
                 self.reporter.reportPlaceholder(self.ast, value_type_def.resolved_type.?.Placeholder);
             } else if (!prop.eql(value_type_def)) {
@@ -4219,6 +4230,30 @@ fn generateZdef(self: *Self, node: Ast.Node.Index, _: ?*Breaks) Error!?*obj.ObjF
     return null;
 }
 
+pub fn populateEmptyCollectionType(self: *Self, value: Ast.Node.Index, target_type: *obj.ObjTypeDef) void {
+    const tags = self.ast.nodes.items(.tag);
+    const components = self.ast.nodes.items(.components);
+
+    // variable: [T] = [<any>] -> variable: [T] = [<T>];
+    if (target_type.def_type == .List and
+        tags[value] == .List and
+        components[value].List.explicit_item_type == null and
+        components[value].List.items.len == 0)
+    {
+        self.ast.nodes.items(.type_def)[value] = target_type;
+    }
+
+    // variable: {K: V} = {<any: any>} -> variable: {K: V} = [<K: V>];
+    if (target_type.def_type == .Map and
+        tags[value] == .Map and
+        components[value].Map.explicit_key_type == null and
+        components[value].Map.explicit_value_type == null and
+        components[value].Map.entries.len == 0)
+    {
+        self.ast.nodes.items(.type_def)[value] = target_type;
+    }
+}
+
 fn OP_SWAP(self: *Self, location: Ast.TokenIndex, slotA: u24, slotB: u24) !void {
     // TODO: both OP_SWAP args could fit in a 32 bit instruction
     try self.emitCodeArg(location, .OP_SWAP, slotA);

diff --git a/src/Parser.zig b/src/Parser.zig
@@ -4619,8 +4619,10 @@ fn dot(self: *Self, can_assign: bool, callee: Ast.Node.Index) Error!Ast.Node.Ind
                 var components = self.ast.nodes.items(.components);
                 if (can_assign and try self.match(.Equal)) {
                     components[dot_node].Dot.member_kind = .Value;
+                    const value = try self.expression(false);
+                    components = self.ast.nodes.items(.components);
                     components[dot_node].Dot.value_or_call_or_enum = .{
-                        .Value = try self.expression(false),
+                        .Value = value,
                     };
                     self.ast.nodes.items(.type_def)[dot_node] = property_type;
                 } else if (try self.match(.LeftParen)) { // Do we call it
@@ -4672,7 +4674,10 @@ fn dot(self: *Self, can_assign: bool, callee: Ast.Node.Index) Error!Ast.Node.Ind
                 const obj_def = object.resolved_type.?.Object;
 
                 const property_field = obj_def.fields.get(member_name);
-                var property_type = (if (property_field) |field| field.type_def else null) orelse obj_def.placeholders.get(member_name);
+                var property_type = (if (property_field) |field|
+                    field.type_def
+                else
+                    null) orelse obj_def.placeholders.get(member_name);
 
                 // Else create placeholder
                 if (property_type == null and self.current_object != null and std.mem.eql(u8, self.current_object.?.name.lexeme, obj_def.name.string)) {
@@ -4736,6 +4741,7 @@ fn dot(self: *Self, can_assign: bool, callee: Ast.Node.Index) Error!Ast.Node.Ind
                     components[dot_node].Dot.value_or_call_or_enum = .{
                         .Value = expr,
                     };
+
                     self.ast.nodes.items(.type_def)[dot_node] = property_type;
                 } else if (try self.match(.LeftParen)) { // If it's a method or placeholder we can call it
                     // `call` will look to the parent node for the function definition
@@ -7424,13 +7430,24 @@ fn varDeclaration(
         const components = self.ast.nodes.items(.components);
         const parsed_type_def = if (parsed_type) |pt| self.ast.nodes.items(.type_def)[pt] else null;
 
-        // [T] variable = [] -> [T] variable = [<T>];
-        if (parsed_type_def != null and parsed_type_def.?.def_type == .List and tags[uvalue] == .List and components[uvalue].List.explicit_item_type == null and components[uvalue].List.items.len == 0) {
+        // var variable: [T] = [<any>] -> var variable: [T] = [<T>];
+        if (parsed_type_def != null and
+            parsed_type_def.?.def_type == .List and
+            tags[uvalue] == .List and
+            components[uvalue].List.explicit_item_type == null and
+            components[uvalue].List.items.len == 0)
+        {
             self.ast.nodes.items(.type_def)[uvalue] = parsed_type_def.?;
         }
 
-        // {K: V} variable = {} -> {K: V} variable = [<K: V>];
-        if (parsed_type_def != null and parsed_type_def.?.def_type == .Map and tags[uvalue] == .Map and components[uvalue].Map.explicit_key_type == null and components[uvalue].Map.explicit_value_type == null and components[uvalue].Map.entries.len == 0) {
+        // var variable: {K: V} = {<any: any>} -> var variable: {K: V} = [<K: V>];
+        if (parsed_type_def != null and
+            parsed_type_def.?.def_type == .Map and
+            tags[uvalue] == .Map and
+            components[uvalue].Map.explicit_key_type == null and
+            components[uvalue].Map.explicit_value_type == null and
+            components[uvalue].Map.entries.len == 0)
+        {
             self.ast.nodes.items(.type_def)[uvalue] = parsed_type_def.?;
         }
     }

diff --git a/src/lib/http.buzz b/src/lib/http.buzz
@@ -207,7 +207,7 @@ export object Request {
     request: ud? = null,
     response: Response? = null,
     method: Method,
-    headers: {str: str}  = {<str str>},
+    headers: {str: str}  = {},
     uri: str = "/",
     body: str? = null,
     collected: bool = false,
@@ -261,7 +261,7 @@ export object Request {
 // Don't change proeprties order
 export object Response {
     status: int = 200,
-    headers: {str: str} = {<str: str>},
+    headers: {str: str} = {},
     body: str? = null,
 
     fun toString() > str {

diff --git a/src/lib/serialize.buzz b/src/lib/serialize.buzz
@@ -36,7 +36,7 @@ export object Boxed {
     /// When wrapped data is an object, object property values are themselves wrapped in a `Boxed`
     fun map() > {str: Boxed}? {
         if (this.data as? {str: any} -> dataMap) {
-            var boxedMap = mut {<str: Boxed>};
+            var boxedMap: mut {str: Boxed} = mut {};
 
             foreach (key, value in dataMap) {
                 boxedMap[key] = Boxed{ data = value };
@@ -51,7 +51,7 @@ export object Boxed {
     /// When wrapped data is a list, list elements are themselves warpped in a `Boxed`
     fun list() > [Boxed]? {
         if (this.data as? [any] -> dataList) {
-            var boxedList = mut [<Boxed>];
+            var boxedList: mut [Boxed] = mut [];
 
             foreach (element in dataList) {
                 boxedList.append(Boxed{ data = element });
@@ -196,7 +196,7 @@ object JsonParser {
     }
 
     mut fun array() > [any] !> JsonParseError, buffer\WriteWhileReadingError {
-        var array = mut [<any>];
+        var array: mut [any] = mut [];
 
         while (true) {
             this.skipWhitespaces();
@@ -220,7 +220,7 @@ object JsonParser {
     }
 
     mut fun map() > {str: any} !> JsonParseError, buffer\WriteWhileReadingError {
-        var map = mut {<str: any>};
+        var map: mut {str: any} = mut {};
 
         while (true) {
             this.skipWhitespaces();

diff --git a/src/lib/testing.buzz b/src/lib/testing.buzz
@@ -62,8 +62,8 @@ export fun oncyan(text: str) => color(text, color: Color.oncyan);
 export fun onwhite(text: str) => color(text, color: Color.onwhite);
 
 export object Tester {
-    tests: mut [bool] = mut [<bool>],
-    asserts: mut [bool] = mut [<bool>],
+    tests: mut [bool] = mut [],
+    asserts: mut [bool] = mut [],
     elapsed: double = 0.0,
     beforeAll: fun (t: Tester) > void?,
     beforeEach: fun (t: Tester) > void?,
@@ -91,8 +91,8 @@ export object Tester {
     }
 
     mut fun reset() > void {
-        this.tests = mut [<bool>];
-        this.asserts = mut [<bool>];
+        this.tests = mut [];
+        this.asserts = mut [];
         this.elapsed = 0.0;
     }
 

diff --git a/tests/011-list-map-properties.buzz b/tests/011-list-map-properties.buzz
@@ -7,9 +7,8 @@ object Hey {
 
 test "List and Map as Object properties" {
     final hey = Hey{
-        ages = [<int>, 1, 2, 3],
+        ages = [1, 2, 3],
         names = {
-            <int: str>,
             1: "hello"
         },
     };

diff --git a/tests/019-is.buzz b/tests/019-is.buzz
@@ -27,8 +27,8 @@ test "`is` operator" {
     std\assert(MyEnum.one is MyEnum, message: "`is` for an enum instance");
     std\assert(myFun is fun (id: int) > int, message: "`is` for a function");
 
-    std\assert([<int>, 1,2,3] is [int], message: "`is` on a list");
-    std\assert({<str: int>, "one": 1} is {str: int}, message: "`is` on a map");
+    std\assert([1,2,3] is [int], message: "`is` on a list");
+    std\assert({"one": 1} is {str: int}, message: "`is` on a map");
     // TODO: should be `fun (MyObj) > bool`
     std\assert(MyObj{}.bound is fun () > bool, message: "`is` on bound method");
 }
diff --git a/tests/032-debug.buzz b/tests/032-debug.buzz
@@ -39,7 +39,7 @@ object MyObject {
         return MyObject{
             name = name,
             age = age,
-            data = Data{ data = [<int>] },
+            data = Data{ data = [] },
         };
     }
 }

diff --git a/tests/037-dead-branches.buzz b/tests/037-dead-branches.buzz
@@ -9,7 +9,7 @@ test "if" {
 }
 
 test "foreach" {
-    foreach (_ in {<str: str>}) {
+    foreach (_ in {}) {
         std\assert(false, message: "unreachable");
     }
 }

diff --git a/tests/041-iterator.buzz b/tests/041-iterator.buzz
@@ -25,7 +25,7 @@ test "finobacci generator" {
 
 object Hello {
     fun getRange() > [int] *> int? {
-        var list = mut [<int>];
+        var list: mut [int] = mut [];
         foreach (i in 0..10) {
             _ = yield i;
 

diff --git a/tests/042-anonymous-objects.buzz b/tests/042-anonymous-objects.buzz
@@ -51,7 +51,7 @@ object A {
 
     fun free() > void {
         foreach (x, y in this.board) {
-            var board = mut [<obj{ x: int }>];
+            var board: mut [obj{ x: int }] = mut [];
 
             board.append(.{ x = x });
         }