DzLox

commit c4e963983d4a234f56bacfb0b0c95e452bee3885
parent b1db7d3cbf3d4f68271b580c4c9adb92f3a766fd
Author: Szymon Mikulicz <szymon.mikulicz@aptiv.com>
Date:   Mon,  9 Sep 2024 15:09:44 +0200

Add for_each to list

Diffstat:
M
zlox/src/list.zig
 | 
39
++++++++++++++++++++-------------------
M
zlox/src/obj/list.zig
 | 
31
+++++++++++++++++++++----------

2 files changed, 41 insertions(+), 29 deletions(-)
diff --git a/zlox/src/list.zig b/zlox/src/list.zig
@@ -74,16 +74,18 @@ pub fn List(T: type) type {
             }
         }
 
-        fn _set(self: *Self, index: usize, val: ?T) Error!void {
+        fn _set(self: *Self, index: usize, val: ?T) Error!bool {
             var idx_rev: isize = @intCast(index);
             var idx: isize = @as(isize, @intCast(self.len)) - idx_rev;
             idx_rev += 1;
+            var isNewVal = false;
 
             if (idx <= 0) {
                 while(idx < 0) : (idx += 1) {
                     try self._push(null);
                 }
                 try self._push(val);
+                isNewVal = true;
             } else if (idx < idx_rev) {
                 var tip = self.tip;
                 while(idx > 1) : (idx -= 1) {
@@ -97,10 +99,10 @@ pub fn List(T: type) type {
                 }
                 end.?.val = val;
             }
-
+            return isNewVal;
         }
 
-        pub fn set(self: *Self, index: usize, val: T) Error!void {
+        pub fn set(self: *Self, index: usize, val: T) Error!bool {
             return self._set(index, val);
         }
 
@@ -109,7 +111,7 @@ pub fn List(T: type) type {
             if (index == self.len - 1) {
                 _ = self.pop() catch unreachable;
             } else {
-                self._set(index, null) catch unreachable;
+                _ = self._set(index, null) catch unreachable;
             }
         }
 
@@ -141,21 +143,6 @@ pub fn List(T: type) type {
             try self.push_end(val);
         }
 
-        pub fn format(self: *const Self, comptime fmt: []const u8, options: std.fmt.FormatOptions, writer: anytype) utils.fn_error(@TypeOf(writer).write)!void {
-            _ = try writer.write("[");
-            var end = self.end;
-            while (end) |el| : (end = el.prev) {
-                if (el.val) |v| {
-                    try v.format(fmt, options, writer);
-                } else {
-                    _ = try writer.write("-");
-                }
-                if (el.prev) |_| _ = try writer.write(", ");
-            }
-            _ = try writer.writeAll("]");
-        }
-
-
         fn _pop(self: *Self) Error!?T {
             if (self.tip) |tip| {
                 if (tip.next) |next| {
@@ -215,5 +202,19 @@ pub fn List(T: type) type {
         pub fn push_end(self: *Self, val: T) Error!void {
             return self._push_end(val);
         }
+
+        pub fn for_each(self: *const Self, arg: anytype, fun: fn (@TypeOf(arg), ?T) void) void {
+            var end = self.end;
+            while (end) |el| : (end = el.prev) {
+                fun(arg, el.val);
+            }
+        }
+
+        pub fn for_each_try(self: *const Self, arg: anytype, fun: anytype) utils.fn_error(fun)!void {
+            var end = self.end;
+            while (end) |el| : (end = el.prev) {
+                try fun(arg, el.val);
+            }
+        }
     };
 }
diff --git a/zlox/src/obj/list.zig b/zlox/src/obj/list.zig
@@ -34,16 +34,27 @@ pub const List = packed struct {
     }
 
     pub fn format(self: *const Self, comptime fmt: []const u8, options: std.fmt.FormatOptions, writer: anytype) utils.fn_error(@TypeOf(writer).write)!void {
-        _ = try writer.write("[");
-        var end = self.list.end;
-        while (end) |el| : (end = el.prev) {
-            if (el.val) |v| {
-                try v.format(fmt, options, writer);
-            } else {
-                _ = try writer.write("-");
+        const Printer = struct {
+            options: std.fmt.FormatOptions,
+            writer: @TypeOf(writer),
+            count: usize,
+
+            pub fn print(this: *@This(), val: ?Value) utils.fn_error(@TypeOf(writer).write)!void {
+                this.count -= 1;
+                if (val) |v| {
+                    try v.format(fmt, this.options, this.writer);
+                } else {
+                    _ = try this.writer.write("-");
+                }
+                if (this.count > 0) _ = try this.writer.write(", ");
             }
-            if (el.prev) |_| _ = try writer.write(", ");
-        }
+
+        };
+
+        var printer = Printer{.options = options, .writer = writer, .count = self.list.len};
+
+        _ = try writer.write("[");
+        try self.list.for_each_try(&printer, Printer.print);
         _ = try writer.writeAll("]");
     }
 
@@ -75,6 +86,6 @@ pub const List = packed struct {
         if (!index.is(Value.number) or index.number < 0) {
             return Error.InvalidArgument;
         }
-        return self.list.set(@intFromFloat(index.number), val);
+        _ = try self.list.set(@intFromFloat(index.number), val);
     }
 };