Merge pull request #4 from Dadido3/typst-0.13.1

Add Typst 0.13.1 to Compatibility list

.github/workflows/lint.yml

@@ -0,0 +1,29 @@
+name: golangci-lint
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+permissions:
+  contents: read
+  # Optional: allow read access to pull request. Use with `only-new-issues` option.
+  # pull-requests: read
+
+jobs:
+  golangci:
+    name: lint
+    runs-on: ubuntu-latest
+    steps:
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: stable
+
+      - name: Check out code
+        uses: actions/checkout@v4
+
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v6
+        with:
+          version: v1.64

.github/workflows/test.yml

@@ -10,7 +10,7 @@ jobs:
     strategy:
       matrix:
         go-version: ['1.23.x']
-        typst-version: ['0.12.0', '0.13.0']
+        typst-version: ['0.12.0', '0.13.0', '0.13.1']
 
     steps:
       - name: Install typst-cli ${{ matrix.typst-version }} from crates.io

.vscode/settings.json

@@ -2,6 +2,7 @@
     "cSpell.words": [
         "Dadido",
         "Foogaloo",
+        "golangci",
         "typst",
         "Vogel"
     ]

README.md

@@ -12,6 +12,7 @@ Supported Typst versions are tested by unit tests to ensure compatibility.
 
 - Typst 0.12.0
 - Typst 0.13.0
+- Typst 0.13.1
 
 While breaking changes may occur, i aim to minimize disruptions.
 Use at your own discretion for production systems.
@@ -20,7 +21,7 @@ Use at your own discretion for production systems.
 
 - PDF, SVG and PNG generation.
 - All Typst parameters are discoverable and documented in [cli-options.go](cli-options.go).
-- Go-to-Typst Object Encoder: Seamlessly inject any Go values (Including `image.Image` with a [wrapper](image.go)) into Typst documents via the provided encoder.
+- Go-to-Typst Value Encoder: Seamlessly inject any Go values (Including `image.Image` with a [wrapper](image.go)) into Typst documents via the provided encoder.
 - Errors from Typst CLI are returned as structured Go error objects with detailed information, such as line numbers and file paths.
 - Uses stdio; No temporary files will be created.
 - Good unit test coverage.

cli-options.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2024 David Vogel
+// Copyright (c) 2024-2025 David Vogel
 //
 // This software is released under the MIT License.
 // https://opensource.org/licenses/MIT
@@ -22,6 +22,14 @@ const (
 	OutputFormatHTML OutputFormat = "html" // this format is only available since 0.13.0
 )
 
+type PDFStandard string
+
+const (
+	PDFStandard1_7  PDFStandard = "1.7"  // PDF 1.7
+	PDFStandardA_2B PDFStandard = "a-2b" // PDF/A-2b
+	PDFStandardA_3B PDFStandard = "a-3b" // PDF/A-3b (Available since Typst 0.13.0 and later)
+)
+
 type CLIOptions struct {
 	Root              string            // Configures the project root (for absolute paths).
 	Input             map[string]string // String key-value pairs visible through `sys.inputs`.
@@ -42,13 +50,10 @@ type CLIOptions struct {
 	Format OutputFormat // The format of the output file, inferred from the extension by default.
 	PPI    int          // The PPI (pixels per inch) to use for PNG export. Defaults to 144.
 
-	// One (or multiple comma-separated) PDF standards that Typst will enforce conformance with.
+	// One (or multiple) PDF standards that Typst will enforce conformance with.
 	//
-	// Possible values:
+	// See typst.PDFStandard for possible values.
-	//
+	PDFStandards []PDFStandard
-	//	- 1.7: PDF 1.7
-	//	- a-2b: PDF/A-2b
-	PDFStandard string
 
 	Custom []string // Custom command line options go here.
 }
@@ -112,9 +117,18 @@ func (c *CLIOptions) Args() (result []string) {
 		result = append(result, "--ppi", strconv.FormatInt(int64(c.PPI), 10))
 	}
 
-	if c.PDFStandard != "" {
+	if len(c.PDFStandards) > 0 {
-		result = append(result, "--pdf-standard", c.PDFStandard)
+		var standards string
+		for i, standard := range c.PDFStandards {
+			if i > 0 {
+				standards += ","
+			}
+			standards += string(standard)
+		}
+		result = append(result, "--pdf-standard", standards)
 	}
 
+	result = append(result, c.Custom...)
+
 	return
 }

cli-options_test.go

@@ -0,0 +1,24 @@
+package typst_test
+
+import (
+	"os"
+	"testing"
+
+	"github.com/Dadido3/go-typst"
+)
+
+func TestCliOptions(t *testing.T) {
+	o := typst.CLIOptions{
+		FontPaths: []string{"somepath/to/somewhere", "another/to/somewhere"},
+	}
+	args := o.Args()
+	if len(args) != 2 {
+		t.Errorf("wrong number of arguments, expected 2, got %d", len(args))
+	}
+	if "--font-path" != args[0] {
+		t.Error("wrong font path option, expected --font-path, got", args[0])
+	}
+	if "somepath/to/somewhere"+string(os.PathListSeparator)+"another/to/somewhere" != args[1] {
+		t.Error("wrong font path option, expected my two paths concatenated, got", args[1])
+	}
+}

cli.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2024 David Vogel
+// Copyright (c) 2024-2025 David Vogel
 //
 // This software is released under the MIT License.
 // https://opensource.org/licenses/MIT
@@ -15,12 +15,12 @@ import (
 // TODO: Add docker support to CLI, by calling docker run instead
 
 type CLI struct {
-	ExecutablePath string // The typst executable path can be overridden here. Otherwise the default path will be used.
+	ExecutablePath string // The Typst executable path can be overridden here. Otherwise the default path will be used.
 }
 
-// TODO: Add method for querying the typst version resulting in a semver object
+// TODO: Add method for querying the Typst version resulting in a semver object
 
-// VersionString returns the version string as returned by typst.
+// VersionString returns the version string as returned by Typst.
 func (c CLI) VersionString() (string, error) {
 	// Get path of executable.
 	execPath := ExecutablePath
@@ -46,7 +46,7 @@ func (c CLI) VersionString() (string, error) {
 	return output.String(), nil
 }
 
-// Compile takes a typst document from input, and renders it into the output writer.
+// Compile takes a Typst document from input, and renders it into the output writer.
 // The options parameter is optional.
 func (c CLI) Compile(input io.Reader, output io.Writer, options *CLIOptions) error {
 	args := []string{"c"}
@@ -80,22 +80,17 @@ func (c CLI) Compile(input io.Reader, output io.Writer, options *CLIOptions) err
 	return nil
 }
 
-// Compile takes a typst document from input, and renders it into the output writer.
+// CompileWithVariables takes a Typst document from input, and renders it into the output writer.
 // The options parameter is optional.
 //
-// Additionally this will inject the given map of variables into the global scope of the typst document.
+// Additionally this will inject the given map of variables into the global scope of the Typst document.
+//
+// Deprecated: You should use InjectValues in combination with the normal Compile method instead.
 func (c CLI) CompileWithVariables(input io.Reader, output io.Writer, options *CLIOptions, variables map[string]any) error {
 	varBuffer := bytes.Buffer{}
 
-	// TODO: Use io.pipe instead of a bytes.Buffer
+	if err := InjectValues(&varBuffer, variables); err != nil {
-
+		return fmt.Errorf("failed to inject values into Typst markup: %w", err)
-	enc := NewVariableEncoder(&varBuffer)
-	for k, v := range variables {
-		varBuffer.WriteString("#let " + CleanIdentifier(k) + " = ")
-		if err := enc.Encode(v); err != nil {
-			return fmt.Errorf("failed to encode variables with key %q: %w", k, err)
-		}
-		varBuffer.WriteRune('\n')
 	}
 
 	reader := io.MultiReader(&varBuffer, input)

cli_unix.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2024 David Vogel
+// Copyright (c) 2024-2025 David Vogel
 //
 // This software is released under the MIT License.
 // https://opensource.org/licenses/MIT
@@ -7,5 +7,5 @@
 
 package typst
 
-// The path to the typst executable.
+// The path to the Typst executable.
 var ExecutablePath = "typst"

cli_windows.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2024 David Vogel
+// Copyright (c) 2024-2025 David Vogel
 //
 // This software is released under the MIT License.
 // https://opensource.org/licenses/MIT
@@ -7,9 +7,9 @@
 
 package typst
 
-// The path to the typst executable.
+// The path to the Typst executable.
 // We assume the executable is in the current working directory.
 //var ExecutablePath = "." + string(filepath.Separator) + filepath.Join("typst.exe")
 
-// The path to the typst executable.
+// The path to the Typst executable.
 var ExecutablePath = "typst.exe"

errors.go

@@ -14,13 +14,13 @@ import (
 // ErrorDetails contains the details of a typst.Error.
 type ErrorDetails struct {
 	Message string // The parsed error message.
-	Path    string // Path of the typst file where the error is located in. Zero value means that there is no further information.
+	Path    string // Path of the Typst file where the error is located in. Zero value means that there is no further information.
 	Line    int    // Line number of the error. Zero value means that there is no further information.
 	Column  int    // Column of the error. Zero value means that there is no further information.
 }
 
-// Error represents a typst error.
+// Error represents an error as returned by Typst.
-// This can contain multiple sub-errors or sub-warnings.
+// This can contain multiple sub-errors or sub-warnings which are listed in the field Details.
 type Error struct {
 	Inner error
 

examples/passing-objects/template.typ

@@ -1,33 +0,0 @@
-#set page(paper: "a4")
-
-// Uncomment to use test data.
-//#import "template-test-data.typ": Data
-
-= List of items
-
-#show table.cell.where(y: 0): strong
-#set table(
-  stroke: (x, y) => if y == 0 {
-    (bottom: 0.7pt + black)
-  },
-)
-
-#table(
-  columns: 5,
-  table.header(
-    [Name],
-    [Size],
-    [Example box],
-    [Created],
-    [Numbers],
-  ),
-  ..for value in Data {
-    (
-      [#value.Name],
-      [#value.Size],
-      box(fill: black, width: 0.1mm * value.Size.X, height: 0.1mm * value.Size.Y),
-      value.Created.display(),
-      [#list(..for num in value.Numbers {([#num],)})],
-    )
-  }
-)

examples/passing-values/README.md

@@ -0,0 +1,13 @@
+# Passing values example
+
+This example demonstrates how to pass values to Typst, which can be useful in rendering custom documents such as reports, invoices, and more.
+
+## How it works
+
+This example follows the [template pattern](https://typst.app/docs/tutorial/making-a-template/) described in the Typst documentation.
+Here is a short overview of the files:
+
+- [template.typ](template.typ) defines a Typst template function that constructs a document based on parameters.
+- [main.go](main.go) shows how to convert/encode Go values into Typst markup, and how to call/render the template with these converted values.
+- [template-preview.typ](template-preview.typ) also invokes the template while providing mock data.
+    This is useful when you want to preview, update or debug the template.

examples/passing-values/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"log"
 	"os"
 	"time"
@@ -8,7 +9,7 @@ import (
 	"github.com/Dadido3/go-typst"
 )
 
-// DataEntry contains fake data to be passed to typst.
+// DataEntry contains data to be passed to Typst.
 type DataEntry struct {
 	Name string
 	Size struct{ X, Y, Z float64 }
@@ -25,21 +26,28 @@ var TestData = []DataEntry{
 }
 
 func main() {
-	typstCLI := typst.CLI{}
+	var markup bytes.Buffer
 
-	r, err := os.Open("template.typ")
+	// Inject Go values as Typst markup.
-	if err != nil {
+	if err := typst.InjectValues(&markup, map[string]any{"data": TestData, "customText": "This data is coming from a Go application."}); err != nil {
-		log.Panicf("Failed to open template file for reading: %v.", err)
+		log.Panicf("Failed to inject values into Typst markup: %v.", err)
 	}
-	defer r.Close()
 
+	// Import the template and invoke the template function with the custom data.
+	// Show is used to replace the current document with whatever content the template function in `template.typ` returns.
+	markup.WriteString(`
+#import "template.typ": template
+#show: doc => template(data, customText)`)
+
+	// Compile the prepared markup with Typst and write the result it into `output.pdf`.
 	f, err := os.Create("output.pdf")
 	if err != nil {
 		log.Panicf("Failed to create output file: %v.", err)
 	}
 	defer f.Close()
 
-	if err := typstCLI.CompileWithVariables(r, f, nil, map[string]any{"Data": TestData}); err != nil {
+	typstCLI := typst.CLI{}
+	if err := typstCLI.Compile(&markup, f, nil); err != nil {
 		log.Panicf("Failed to compile document: %v.", err)
 	}
 }

examples/passing-values/main_test.go

@@ -0,0 +1,16 @@
+package main
+
+import (
+	"testing"
+)
+
+// Run the example as a test.
+func TestMain(t *testing.T) {
+	defer func() {
+		if r := recover(); r != nil {
+			t.Error(r)
+		}
+	}()
+
+	main()
+}

examples/passing-values/template-preview.typ

@@ -1,5 +1,12 @@
-#let Data = (
+// Prepare data that will be used as preview.
+#let data = (
   (Name: "Bell", Size: (X: 80, Y: 40, Z: 40), Created: datetime(year: 2010, month: 12, day: 1, hour: 12, minute: 13, second: 14), Numbers: (1, 2, 3)),
   (Name: "Bell", Size: (X: 80, Y: 40, Z: 40), Created: datetime(year: 2010, month: 12, day: 1, hour: 12, minute: 13, second: 14), Numbers: (10, 12, 15)),
   (Name: "Bell", Size: (X: 80, Y: 40, Z: 40), Created: datetime(year: 2010, month: 12, day: 1, hour: 12, minute: 13, second: 14), Numbers: (100, 109, 199, 200)),
 )
+
+#let customText = "Hey, this is example data to test the template."
+
+// Invoke the template with the preview data and replace this whole document with the result.
+#import "template.typ": template
+#show: doc => template(data, customText)

examples/passing-values/template.typ

@@ -0,0 +1,36 @@
+#let template(data, customText) = {
+  set page(paper: "a4")
+
+  [= Example]
+
+  customText
+
+  [== List of items]
+
+  show table.cell.where(y: 0): strong
+  set table(
+    stroke: (x, y) => if y == 0 {
+      (bottom: 0.7pt + black)
+    },
+  )
+
+  table(
+    columns: 5,
+    table.header(
+      [Name],
+      [Size],
+      [Example box],
+      [Created],
+      [Numbers],
+    ),
+    ..for value in data {
+      (
+        [#value.Name],
+        [#value.Size],
+        box(fill: black, width: 0.1mm * value.Size.X, height: 0.1mm * value.Size.Y),
+        value.Created.display(),
+        [#list(..for num in value.Numbers {([#num],)})],
+      )
+    }
+  )
+}

examples/simple/README.md

@@ -0,0 +1,12 @@
+# Simple example
+
+This example shows how to render Typst documents directly from strings in Go.
+
+## The pros and cons
+
+The main advantage of this method is that it's really easy to set up.
+In the most simple case you build your Typst markup by concatenating strings, or by using `fmt.Sprintf`.
+
+The downside is that the final Typst markup is only generated on demand.
+This means that you can't easily use the existing Typst tooling to write, update or debug your Typst markup.
+Especially as your your documents get more complex, you should switch to other methods.

examples/simple/main.go

@@ -0,0 +1,37 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+	"os"
+	"time"
+
+	"github.com/Dadido3/go-typst"
+)
+
+func main() {
+	// Convert a time.Time value into Typst markup.
+	date, err := typst.MarshalValue(time.Now())
+	if err != nil {
+		log.Panicf("Failed to marshal date into Typst markup: %v", err)
+	}
+
+	// Write Typst markup into buffer.
+	var markup bytes.Buffer
+	fmt.Fprintf(&markup, `= Hello world
+
+This document was created at #%s.display() using typst-go.`, date)
+
+	// Compile the prepared markup with Typst and write the result it into `output.pdf`.
+	f, err := os.Create("output.pdf")
+	if err != nil {
+		log.Panicf("Failed to create output file: %v.", err)
+	}
+	defer f.Close()
+
+	typstCLI := typst.CLI{}
+	if err := typstCLI.Compile(&markup, f, nil); err != nil {
+		log.Panic("failed to compile document: %w", err)
+	}
+}

examples/simple/main_test.go

@@ -0,0 +1,16 @@
+package main
+
+import (
+	"testing"
+)
+
+// Run the example as a test.
+func TestMain(t *testing.T) {
+	defer func() {
+		if r := recover(); r != nil {
+			t.Error(r)
+		}
+	}()
+
+	main()
+}

identifier.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2024 David Vogel
+// Copyright (c) 2024-2025 David Vogel
 //
 // This software is released under the MIT License.
 // https://opensource.org/licenses/MIT
@@ -11,7 +11,7 @@ import (
 	"github.com/smasher164/xid"
 )
 
-// CleanIdentifier will return the input cleaned up in a way so that it can safely be used as a typst identifier.
+// CleanIdentifier will return the input cleaned up in a way so that it can safely be used as a Typst identifier.
 // This function will replace all illegal characters, which means collisions are possible in some cases.
 //
 // See https://github.com/typst/typst/blob/76c24ee6e35715cd14bb892d7b6b8d775c680bf7/crates/typst-syntax/src/lexer.rs#L932 for details.

image.go

@@ -1,3 +1,8 @@
+// Copyright (c) 2024-2025 David Vogel
+//
+// This software is released under the MIT License.
+// https://opensource.org/licenses/MIT
+
 package typst
 
 import (
@@ -8,12 +13,12 @@ import (
 	"strconv"
 )
 
-// Image can be used to encode any image.Image into a typst image.
+// Image can be used to encode any image.Image into a Typst image.
 //
-// For this, just wrap any image.Image with this type before passing it to MarshalVariable or a VariableEncoder.
+// For this, just wrap any image.Image with this type before passing it to MarshalValue or a ValueEncoder.
 type Image struct{ image.Image }
 
-func (i Image) MarshalTypstVariable() ([]byte, error) {
+func (i Image) MarshalTypstValue() ([]byte, error) {
 	var buffer bytes.Buffer
 
 	if err := png.Encode(&buffer, i); err != nil {
@@ -22,8 +27,10 @@ func (i Image) MarshalTypstVariable() ([]byte, error) {
 
 	// TODO: Make image encoding more efficient: Use reader/writer, baseXX encoding
 
+	// TODO: Consider using raw pixel encoding instead of PNG
+
 	var buf bytes.Buffer
-	buf.WriteString("image.decode(bytes((")
+	buf.WriteString("image.decode(bytes((") // TODO: Pass bytes directly to image once Typst 0.12.0 is not supported anymore
 	for _, b := range buffer.Bytes() {
 		buf.WriteString(strconv.FormatUint(uint64(b), 10) + ",")
 	}

image_test.go

@@ -33,18 +33,26 @@ func (p *testImage) Opaque() bool {
 }
 
 func TestImage(t *testing.T) {
-	img := &testImage{image.Rect(0, 0, 255, 255)}
+	img := &testImage{image.Rect(0, 0, 256, 256)}
 
 	// Wrap image.
 	typstImage := typst.Image{img}
 
 	cli := typst.CLI{}
 
-	r := bytes.NewBufferString(`= Image test
+	var r bytes.Buffer
 
-#TestImage`)
+	if err := typst.InjectValues(&r, map[string]any{"TestImage": typstImage}); err != nil {
+		t.Fatalf("Failed to inject values into Typst markup: %v.", err)
+	}
 
-	if err := cli.CompileWithVariables(r, io.Discard, nil, map[string]any{"TestImage": typstImage}); err != nil {
+	r.WriteString(`= Image test
+
+#TestImage
+
+#assert(type(TestImage) == content, message: "TestImage is not of expected type: got " + str(type(TestImage)) + ", want content")`) // TODO: Add another assertion for the image width and height as soon as it's possible to query that
+
+	if err := cli.Compile(&r, io.Discard, nil); err != nil {
 		t.Fatalf("Failed to compile document: %v.", err)
 	}
 }

util.go

@@ -0,0 +1,47 @@
+// Copyright (c) 2025 David Vogel
+//
+// This software is released under the MIT License.
+// https://opensource.org/licenses/MIT
+
+package typst
+
+import (
+	"fmt"
+	"io"
+	"maps"
+	"slices"
+)
+
+// InjectValues will write the given key-value pairs as Typst markup into output.
+// This can be used to inject Go values into Typst documents.
+//
+// Every key in values needs to be a valid identifier, otherwise this function will return an error.
+// Every value in values will be marshaled according to ValueEncoder into equivalent Typst markup.
+//
+// Passing {"foo": 1, "bar": 60 * time.Second} as values will produce the following output:
+//
+//	#let foo = 1
+//	#let bar = duration(seconds: 60)
+func InjectValues(output io.Writer, values map[string]any) error {
+	enc := NewValueEncoder(output)
+
+	// We will have to iterate over the sorted list of map keys.
+	// Otherwise the output is not deterministic, and tests will fail randomly.
+	for _, k := range slices.Sorted(maps.Keys(values)) {
+		v := values[k]
+		if !IsIdentifier(k) {
+			return fmt.Errorf("%q is not a valid identifier", k)
+		}
+		if _, err := output.Write([]byte("#let " + CleanIdentifier(k) + " = ")); err != nil {
+			return err
+		}
+		if err := enc.Encode(v); err != nil {
+			return fmt.Errorf("failed to encode values with key %q: %w", k, err)
+		}
+		if _, err := output.Write([]byte("\n")); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

util_test.go

@@ -0,0 +1,36 @@
+package typst
+
+import (
+	"bytes"
+	"testing"
+	"time"
+)
+
+func TestInjectValues(t *testing.T) {
+	type args struct {
+		values map[string]any
+	}
+	tests := []struct {
+		name       string
+		args       args
+		wantOutput string
+		wantErr    bool
+	}{
+		{"empty", args{values: nil}, "", false},
+		{"nil", args{values: map[string]any{"foo": nil}}, "#let foo = none\n", false},
+		{"example", args{values: map[string]any{"foo": 1, "bar": 60 * time.Second}}, "#let bar = duration(seconds: 60)\n#let foo = 1\n", false},
+		{"invalid identifier", args{values: map[string]any{"foo😀": 1}}, "", true},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			output := &bytes.Buffer{}
+			if err := InjectValues(output, tt.args.values); (err != nil) != tt.wantErr {
+				t.Errorf("InjectValues() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if gotOutput := output.String(); gotOutput != tt.wantOutput {
+				t.Errorf("InjectValues() = %v, want %v", gotOutput, tt.wantOutput)
+			}
+		})
+	}
+}

value-encoder.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2024 David Vogel
+// Copyright (c) 2024-2025 David Vogel
 //
 // This software is released under the MIT License.
 // https://opensource.org/licenses/MIT
@@ -18,11 +18,11 @@ import (
 	"time"
 )
 
-// MarshalVariable takes any go type and returns a typst markup representation as a byte slice.
+// MarshalValue takes any Go type and returns a Typst markup representation as a byte slice.
-func MarshalVariable(v any) ([]byte, error) {
+func MarshalValue(v any) ([]byte, error) {
 	var buf bytes.Buffer
 
-	enc := NewVariableEncoder(&buf)
+	enc := NewValueEncoder(&buf)
 	if err := enc.Encode(v); err != nil {
 		return nil, err
 	}
@@ -30,37 +30,37 @@ func MarshalVariable(v any) ([]byte, error) {
 	return buf.Bytes(), nil
 }
 
-// VariableMarshaler can be implemented by types to support custom typst marshaling.
+// ValueMarshaler can be implemented by types to support custom Typst marshaling.
-type VariableMarshaler interface {
+type ValueMarshaler interface {
-	MarshalTypstVariable() ([]byte, error)
+	MarshalTypstValue() ([]byte, error)
 }
 
-type VariableEncoder struct {
+type ValueEncoder struct {
 	indentLevel int
 
 	writer io.Writer
 }
 
-// NewVariableEncoder returns a new encoder that writes into w.
+// NewValueEncoder returns a new encoder that writes into w.
-func NewVariableEncoder(w io.Writer) *VariableEncoder {
+func NewValueEncoder(w io.Writer) *ValueEncoder {
-	return &VariableEncoder{
+	return &ValueEncoder{
 		writer: w,
 	}
 }
 
-func (e *VariableEncoder) Encode(v any) error {
+func (e *ValueEncoder) Encode(v any) error {
 	return e.marshal(reflect.ValueOf(v))
 }
 
-func (e *VariableEncoder) writeString(s string) error {
+func (e *ValueEncoder) writeString(s string) error {
 	return e.writeBytes([]byte(s))
 }
 
-func (e *VariableEncoder) writeRune(r rune) error {
+func (e *ValueEncoder) writeRune(r rune) error {
 	return e.writeBytes([]byte{byte(r)})
 }
 
-func (e *VariableEncoder) writeStringLiteral(s []byte) error {
+func (e *ValueEncoder) writeStringLiteral(s []byte) error {
 	dst := make([]byte, 0, len(s)+5)
 
 	dst = append(dst, '"')
@@ -85,7 +85,7 @@ func (e *VariableEncoder) writeStringLiteral(s []byte) error {
 	return e.writeBytes(dst)
 }
 
-func (e *VariableEncoder) writeBytes(b []byte) error {
+func (e *ValueEncoder) writeBytes(b []byte) error {
 	if _, err := e.writer.Write(b); err != nil {
 		return fmt.Errorf("failed to write into writer: %w", err)
 	}
@@ -93,11 +93,11 @@ func (e *VariableEncoder) writeBytes(b []byte) error {
 	return nil
 }
 
-func (e *VariableEncoder) writeIndentationCharacters() error {
+func (e *ValueEncoder) writeIndentationCharacters() error {
 	return e.writeBytes(slices.Repeat([]byte{' ', ' '}, e.indentLevel))
 }
 
-func (e *VariableEncoder) marshal(v reflect.Value) error {
+func (e *ValueEncoder) marshal(v reflect.Value) error {
 	if !v.IsValid() {
 		return e.writeString("none")
 		//return fmt.Errorf("invalid reflect.Value %v", v)
@@ -113,8 +113,7 @@ func (e *VariableEncoder) marshal(v reflect.Value) error {
 		return nil
 	case *time.Time:
 		if i == nil {
-			e.writeString("none")
+			return e.writeString("none")
-			return nil
 		}
 		if err := e.encodeTime(*i); err != nil {
 			return err
@@ -127,8 +126,7 @@ func (e *VariableEncoder) marshal(v reflect.Value) error {
 		return nil
 	case *time.Duration:
 		if i == nil {
-			e.writeString("none")
+			return e.writeString("none")
-			return nil
 		}
 		if err := e.encodeDuration(*i); err != nil {
 			return err
@@ -136,8 +134,18 @@ func (e *VariableEncoder) marshal(v reflect.Value) error {
 		return nil
 	}
 
-	// TODO: Handle images, maybe create a wrapper type that does this
+	if t.Implements(reflect.TypeFor[ValueMarshaler]()) {
+		if m, ok := v.Interface().(ValueMarshaler); ok {
+			bytes, err := m.MarshalTypstValue()
+			if err != nil {
+				return fmt.Errorf("error calling MarshalTypstValue for type %s: %w", t.String(), err)
+			}
+			return e.writeBytes(bytes)
+		}
+		return e.writeString("none")
+	}
 
+	// TODO: Remove this in a future update, it's only here for compatibility reasons
 	if t.Implements(reflect.TypeFor[VariableMarshaler]()) {
 		if m, ok := v.Interface().(VariableMarshaler); ok {
 			bytes, err := m.MarshalTypstVariable()
@@ -224,11 +232,11 @@ func (e *VariableEncoder) marshal(v reflect.Value) error {
 	return err
 }
 
-func (e *VariableEncoder) encodeString(v reflect.Value) error {
+func (e *ValueEncoder) encodeString(v reflect.Value) error {
 	return e.writeStringLiteral([]byte(v.String()))
 }
 
-func (e *VariableEncoder) encodeStruct(v reflect.Value, t reflect.Type) error {
+func (e *ValueEncoder) encodeStruct(v reflect.Value, t reflect.Type) error {
 	if v.NumField() == 0 {
 		return e.writeString("()")
 	}
@@ -278,7 +286,7 @@ func (e *VariableEncoder) encodeStruct(v reflect.Value, t reflect.Type) error {
 	return e.writeRune(')')
 }
 
-func (e *VariableEncoder) resolveKeyName(v reflect.Value) (string, error) {
+func (e *ValueEncoder) resolveKeyName(v reflect.Value) (string, error) {
 	// From encoding/json/encode.go.
 	if v.Kind() == reflect.String {
 		return v.String(), nil
@@ -299,7 +307,7 @@ func (e *VariableEncoder) resolveKeyName(v reflect.Value) (string, error) {
 	return "", fmt.Errorf("unsupported map key type %q", v.Type().String())
 }
 
-func (e *VariableEncoder) encodeMap(v reflect.Value) error {
+func (e *ValueEncoder) encodeMap(v reflect.Value) error {
 	if v.Len() == 0 {
 		return e.writeString("()")
 	}
@@ -359,12 +367,12 @@ func (e *VariableEncoder) encodeMap(v reflect.Value) error {
 	return e.writeRune(')')
 }
 
-func (e *VariableEncoder) EncodeByteSlice(bb []byte) error {
+func (e *ValueEncoder) EncodeByteSlice(bb []byte) error {
 	if err := e.writeString("bytes(("); err != nil {
 		return err
 	}
 
-	// TODO: Encode byte slice via base64 or similar and use a typst package to convert it into the corresponding bytes type
+	// TODO: Encode byte slice via base64 or similar and use a Typst package to convert it into the corresponding bytes type
 
 	for i, b := range bb {
 		if i > 0 {
@@ -387,7 +395,7 @@ func (e *VariableEncoder) EncodeByteSlice(bb []byte) error {
 	return e.writeString("))")
 }
 
-func (e *VariableEncoder) encodeSlice(v reflect.Value, t reflect.Type) error {
+func (e *ValueEncoder) encodeSlice(v reflect.Value, t reflect.Type) error {
 
 	// Special case for byte slices.
 	if t.Elem().Kind() == reflect.Uint8 {
@@ -419,7 +427,7 @@ func (e *VariableEncoder) encodeSlice(v reflect.Value, t reflect.Type) error {
 	return e.writeRune(')')
 }
 
-func (e *VariableEncoder) encodeArray(v reflect.Value) error {
+func (e *ValueEncoder) encodeArray(v reflect.Value) error {
 	if err := e.writeRune('('); err != nil {
 		return err
 	}
@@ -445,7 +453,7 @@ func (e *VariableEncoder) encodeArray(v reflect.Value) error {
 	return e.writeRune(')')
 }
 
-func (e *VariableEncoder) encodeTime(t time.Time) error {
+func (e *ValueEncoder) encodeTime(t time.Time) error {
 	return e.writeString(fmt.Sprintf("datetime(year: %d, month: %d, day: %d, hour: %d, minute: %d, second: %d)",
 		t.Year(),
 		t.Month(),
@@ -456,6 +464,6 @@ func (e *VariableEncoder) encodeTime(t time.Time) error {
 	))
 }
 
-func (e *VariableEncoder) encodeDuration(d time.Duration) error {
+func (e *ValueEncoder) encodeDuration(d time.Duration) error {
 	return e.writeString(fmt.Sprintf("duration(seconds: %d)", int(math.Round(d.Seconds()))))
 }

value-encoder_test.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2024 David Vogel
+// Copyright (c) 2024-2025 David Vogel
 //
 // This software is released under the MIT License.
 // https://opensource.org/licenses/MIT
@@ -18,7 +18,7 @@ import (
 	"github.com/google/go-cmp/cmp"
 )
 
-func TestMarshalVariable(t *testing.T) {
+func TestMarshalValue(t *testing.T) {
 	tests := []struct {
 		name    string
 		arg     any
@@ -31,33 +31,33 @@ func TestMarshalVariable(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			got, err := typst.MarshalVariable(tt.arg)
+			got, err := typst.MarshalValue(tt.arg)
 			if (err != nil) != tt.wantErr {
-				t.Errorf("MarshalVariable() error = %v, wantErr %v", err, tt.wantErr)
+				t.Errorf("MarshalValue() error = %v, wantErr %v", err, tt.wantErr)
 				return
 			}
 			if !reflect.DeepEqual(got, tt.want) {
-				t.Errorf("MarshalVariable() = %v, want %v", got, tt.want)
+				t.Errorf("MarshalValue() = %v, want %v", got, tt.want)
 			}
 		})
 	}
 }
 
-type VariableMarshalerType []byte
+type ValueMarshalerType []byte
 
-func (v VariableMarshalerType) MarshalTypstVariable() ([]byte, error) {
+func (v ValueMarshalerType) MarshalTypstValue() ([]byte, error) {
 	result := append([]byte{'"'}, v...)
 	result = append(result, '"')
 
 	return result, nil
 }
 
-type VariableMarshalerTypePointer []byte
+type ValueMarshalerTypePointer []byte
 
-var variableMarshalerTypePointer = VariableMarshalerTypePointer("test")
+var valueMarshalerTypePointer = ValueMarshalerTypePointer("test")
-var variableMarshalerTypePointerNil = VariableMarshalerTypePointer(nil)
+var valueMarshalerTypePointerNil = ValueMarshalerTypePointer(nil)
 
-func (v *VariableMarshalerTypePointer) MarshalTypstVariable() ([]byte, error) {
+func (v *ValueMarshalerTypePointer) MarshalTypstValue() ([]byte, error) {
 	if v != nil {
 		result := append([]byte{'"'}, *v...)
 		result = append(result, '"')
@@ -87,7 +87,7 @@ func (v *TextMarshalerTypePointer) MarshalText() ([]byte, error) {
 	return nil, fmt.Errorf("no data")
 }
 
-func TestVariableEncoder(t *testing.T) {
+func TestValueEncoder(t *testing.T) {
 
 	tests := []struct {
 		name    string
@@ -156,11 +156,11 @@ func TestVariableEncoder(t *testing.T) {
 		{"byte slice 1", []byte{1}, false, `bytes((1,))`},
 		{"byte slice empty", []byte{}, false, `bytes(())`},
 		{"byte slice nil", []byte(nil), false, `bytes(())`},
-		{"MarshalTypstVariable value", VariableMarshalerType("test"), false, `"test"`},
+		{"MarshalTypstValue value", ValueMarshalerType("test"), false, `"test"`},
-		{"MarshalTypstVariable value nil", VariableMarshalerType(nil), false, `""`},
+		{"MarshalTypstValue value nil", ValueMarshalerType(nil), false, `""`},
-		{"MarshalTypstVariable pointer", &variableMarshalerTypePointer, false, `"test"`},
+		{"MarshalTypstValue pointer", &valueMarshalerTypePointer, false, `"test"`},
-		{"MarshalTypstVariable pointer nil", &variableMarshalerTypePointerNil, false, `""`},
+		{"MarshalTypstValue pointer nil", &valueMarshalerTypePointerNil, false, `""`},
-		{"MarshalTypstVariable nil pointer", struct{ A *VariableMarshalerTypePointer }{nil}, true, ``},
+		{"MarshalTypstValue nil pointer", struct{ A *ValueMarshalerTypePointer }{nil}, true, ``},
 		{"MarshalText value", TextMarshalerType("test"), false, `"test"`},
 		{"MarshalText value nil", TextMarshalerType(nil), false, `""`},
 		{"MarshalText pointer", &textMarshalerTypePointer, false, `"test"`},
@@ -179,12 +179,12 @@ func TestVariableEncoder(t *testing.T) {
 			t.Parallel()
 
 			var result bytes.Buffer
-			vEnc := typst.NewVariableEncoder(&result)
+			vEnc := typst.NewValueEncoder(&result)
 
 			err := vEnc.Encode(tt.params)
 			switch {
 			case err != nil && !tt.wantErr:
-				t.Fatalf("Failed to encode typst variables: %v", err)
+				t.Fatalf("Failed to encode Typst values: %v", err)
 			case err == nil && tt.wantErr:
 				t.Fatalf("Expected error, but got none")
 			}
@@ -199,7 +199,7 @@ func TestVariableEncoder(t *testing.T) {
 				input := strings.NewReader("#" + result.String())
 				var output bytes.Buffer
 				if err := typstCLI.Compile(input, &output, nil); err != nil {
-					t.Errorf("Failed to compile generated typst markup: %v", err)
+					t.Errorf("Failed to compile generated Typst markup: %v", err)
 				}
 			}
 		})

variable-encoder-compat.go

@@ -0,0 +1,21 @@
+// Copyright (c) 2025 David Vogel
+//
+// This software is released under the MIT License.
+// https://opensource.org/licenses/MIT
+
+package typst
+
+import "io"
+
+// This exists for compatibility reasons.
+
+// Deprecated: Use NewValueEncoder instead, as this will be removed in a future version.
+func NewVariableEncoder(w io.Writer) *ValueEncoder { return NewValueEncoder(w) }
+
+// Deprecated: Use MarshalValue instead, as this will be removed in a future version.
+func MarshalVariable(v any) ([]byte, error) { return MarshalValue(v) }
+
+// Deprecated: Use ValueMarshaler interface instead, as this will be removed in a future version.
+type VariableMarshaler interface {
+	MarshalTypstVariable() ([]byte, error)
+}