Update to work with Zig 0.15

[yoshibox]

Updated to Zig's ArrayListUnmanaged as it's the new default
Make the formatting explicit: "{}" -> "{f}"
Changed the svg.writeTo function to accept a writer's interface and flush at the end

[Sivecano]

this seem useful

[Sivecano]

the documentation should probably be updated.

a bunch of writer-consuming functions like svg.writeTo should also use the new Reader/Writer interface instead of being generic.
this can cause problems since it will automatically cast pointers to const pointers.

this also allows for error sets better than anyerror.

[yoshibox]

I remember updating the examples in the readme, did I miss something ?

I forgot to change the writeTo's function signatures, since it was working I did not look further, does this look right to you:
old: pub fn writeTo(self: *const Kind, writer: anytype) anyerror!void {
new: pub fn writeTo(self: *const Kind, writer: *std.Io.Writer) std.Io.Writer.Error!void

[Sivecano]

yeah, I think that looks about right. there's no non-writer errors in this, right?
(I guess the compiler would tell you)

[Sivecano]

This is what I got after running some sed scripts. seems to work. but I suppose I should test it properly

diff --git a/src/svg/Circle.zig b/src/svg/Circle.zig
index 53e6dcf..5bd26d2 100644
--- a/src/svg/Circle.zig
+++ b/src/svg/Circle.zig
@@ -44,7 +44,7 @@ pub fn init(options: Options) Circle {
 }
 
 /// Write the circle to the given writer
-pub fn writeTo(self: *const Circle, writer: anytype) anyerror!void {
+pub fn writeTo(self: *const Circle, writer: *std.Io.Writer) std.Io.Writer.Error!void {
     try writer.writeAll("<circle ");
     try writer.print("cx=\"{f}\" ", .{self.options.center_x});
     try writer.print("cy=\"{f}\" ", .{self.options.center_y});
diff --git a/src/svg/Line.zig b/src/svg/Line.zig
index 99de75b..a62bc19 100644
--- a/src/svg/Line.zig
+++ b/src/svg/Line.zig
@@ -18,7 +18,7 @@ pub const LineCap = enum {
     round,
     square,
 
-    pub fn format(self: LineCap, writer: anytype) !void {
+    pub fn format(self: LineCap, writer: *std.Io.Writer) !void {
         switch (self) {
             .butt => try writer.writeAll("butt"),
             .round => try writer.writeAll("round"),
@@ -62,7 +62,7 @@ pub fn init(options: Options) Line {
 }
 
 /// Write the line to the given writer
-pub fn writeTo(self: *const Line, writer: anytype) anyerror!void {
+pub fn writeTo(self: *const Line, writer: *std.Io.Writer) std.Io.Writer.Error!void {
     try writer.writeAll("<line ");
     try writer.print("x1=\"{f}\" ", .{self.options.x1});
     try writer.print("y1=\"{f}\" ", .{self.options.y1});
diff --git a/src/svg/Path.zig b/src/svg/Path.zig
index 4287902..c2c43a7 100644
--- a/src/svg/Path.zig
+++ b/src/svg/Path.zig
@@ -129,7 +129,7 @@ pub const Command = union(enum) {
     ClosePath: void,
 
     /// Write the command to the given writer
-    pub fn writeTo(self: *const Command, writer: anytype) anyerror!void {
+    pub fn writeTo(self: *const Command, writer: *std.Io.Writer) std.Io.Writer.Error!void {
         switch (self.*) {
             .MoveTo => {
                 try writer.print("M {d} {d}", .{ self.MoveTo.x, self.MoveTo.y });
@@ -283,7 +283,7 @@ pub fn deinit(self: *const Path) void {
 }
 
 /// Write the path to the given writer
-pub fn writeTo(self: *const Path, writer: anytype) anyerror!void {
+pub fn writeTo(self: *const Path, writer: *std.Io.Writer) std.Io.Writer.Error!void {
     try writer.writeAll("<path");
     if (self.options.commands) |commands| {
         try writer.writeAll(" d=\"");
diff --git a/src/svg/Polyline.zig b/src/svg/Polyline.zig
index 0e092fd..a2b7892 100644
--- a/src/svg/Polyline.zig
+++ b/src/svg/Polyline.zig
@@ -51,7 +51,7 @@ pub fn deinit(self: *const Polyline) void {
 }
 
 /// Write the Polyline to the given writer.
-pub fn writeTo(self: *const Polyline, writer: anytype) anyerror!void {
+pub fn writeTo(self: *const Polyline, writer: *std.Io.Writer) std.Io.Writer.Error!void {
     try writer.writeAll("<polyline ");
     if (self.options.points) |points| {
         try writer.writeAll("points=\"");
diff --git a/src/svg/Rect.zig b/src/svg/Rect.zig
index 43d1134..89293c0 100644
--- a/src/svg/Rect.zig
+++ b/src/svg/Rect.zig
@@ -50,7 +50,7 @@ pub fn init(options: Options) Rect {
 }
 
 /// Write the rectangle to the given writer
-pub fn writeTo(self: *const Rect, writer: anytype) anyerror!void {
+pub fn writeTo(self: *const Rect, writer: *std.Io.Writer) std.Io.Writer.Error!void {
     try writer.writeAll("<rect ");
     try writer.print("x=\"{f}\" ", .{self.options.x});
     try writer.print("y=\"{f}\" ", .{self.options.y});
diff --git a/src/svg/SVG.zig b/src/svg/SVG.zig
index b3f2075..04b5622 100644
--- a/src/svg/SVG.zig
+++ b/src/svg/SVG.zig
@@ -89,7 +89,7 @@ const SVG_HEADER =
 ;
 
 /// Write the SVG to the given writer
-pub fn writeTo(self: *const SVG, writer: anytype) anyerror!void {
+pub fn writeTo(self: *const SVG, writer: *std.Io.Writer) std.Io.Writer.Error!void {
     // Write the header
     try writer.print(SVG_HEADER, .{
         self.width,
diff --git a/src/svg/Text.zig b/src/svg/Text.zig
index 3d3ffb4..a88daac 100644
--- a/src/svg/Text.zig
+++ b/src/svg/Text.zig
@@ -46,7 +46,7 @@ pub const FontSize = union(enum) {
     /// Math value
     math: void,
 
-    pub fn format(self: FontSize, writer: anytype) !void {
+    pub fn format(self: FontSize, writer: *std.Io.Writer) !void {
         switch (self) {
             .pixel => |value| try writer.print("{d}px", .{value}),
             .em => |value| try writer.print("{d}em", .{value}),
@@ -95,7 +95,7 @@ pub const FontWeight = enum {
     /// The bolder font weight
     bolder,
 
-    pub fn format(self: FontWeight, writer: anytype) !void {
+    pub fn format(self: FontWeight, writer: *std.Io.Writer) !void {
         switch (self) {
             .normal => try writer.writeAll("normal"),
             .bold => try writer.writeAll("bold"),
@@ -123,7 +123,7 @@ pub const TextAnchor = enum {
     /// The end anchor
     end,
 
-    pub fn format(self: TextAnchor, writer: anytype) !void {
+    pub fn format(self: TextAnchor, writer: *std.Io.Writer) !void {
         switch (self) {
             .start => try writer.writeAll("start"),
             .middle => try writer.writeAll("middle"),
@@ -159,7 +159,7 @@ pub const DominantBaseline = enum {
     /// The text before edge baseline
     text_before_edge,
 
-    pub fn format(self: DominantBaseline, writer: anytype) !void {
+    pub fn format(self: DominantBaseline, writer: *std.Io.Writer) !void {
         switch (self) {
             .auto => try writer.writeAll("auto"),
             .use_script => try writer.writeAll("use-script"),
@@ -235,7 +235,7 @@ pub fn deinit(self: *const Text) void {
 }
 
 /// Write the text to the given writer
-pub fn writeTo(self: *const Text, writer: anytype) anyerror!void {
+pub fn writeTo(self: *const Text, writer: *std.Io.Writer) std.Io.Writer.Error!void {
     try writer.writeAll("<text ");
     try writer.print("x=\"{f}\" ", .{self.options.x});
     try writer.print("y=\"{f}\" ", .{self.options.y});
diff --git a/src/svg/kind.zig b/src/svg/kind.zig
index b1e6931..40833ee 100644
--- a/src/svg/kind.zig
+++ b/src/svg/kind.zig
@@ -21,7 +21,7 @@ pub const Kind = union(enum) {
     path: SVG.Path,
 
     /// Write the Kind to the given writer
-    pub fn writeTo(self: *const Kind, writer: anytype) anyerror!void {
+    pub fn writeTo(self: *const Kind, writer: *std.Io.Writer) std.Io.Writer.Error!void {
         try switch (self.*) {
             .line => |line| line.writeTo(writer),
             .rect => |rect| rect.writeTo(writer),
diff --git a/src/svg/util/length.zig b/src/svg/util/length.zig
index 16305fa..0e9e080 100644
--- a/src/svg/util/length.zig
+++ b/src/svg/util/length.zig
@@ -9,7 +9,7 @@ pub const LengthPercentAuto = union(enum) {
     /// Automatic length
     auto: void,
 
-    pub fn format(self: LengthPercentAuto, writer: anytype) !void {
+    pub fn format(self: LengthPercentAuto, writer: *std.Io.Writer) !void {
         switch (self) {
             .pixel => |value| try writer.print("{d}", .{value}),
             .percent => |value| try writer.print("{d}%", .{value}),
@@ -25,7 +25,7 @@ pub const LengthPercent = union(enum) {
     /// The length in percent (of the parent).
     percent: f32,
 
-    pub fn format(self: LengthPercent, writer: anytype) !void {
+    pub fn format(self: LengthPercent, writer: *std.Io.Writer) !void {
         switch (self) {
             .pixel => |value| try writer.print("{d}", .{value}),
             .percent => |value| try writer.print("{d}%", .{value}),

[yoshibox]

Yes the std.Io.Writer.Error is the error set return by .write and .flush.
I pushed the modifications

[Sivecano]

I remember updating the examples in the readme, did I miss something ?

Only the this is developed for zig 0.13 disclaimer at the top. should probably say 0.15.2