Proof of concept: Some niceties for Kotlin programmers.

flexmark-util-data/pom.xml

@@ -12,6 +12,10 @@
     <description>flexmark-java data utility classes</description>
 
     <dependencies>
+        <dependency>
+            <groupId>org.jetbrains.kotlin</groupId>
+            <artifactId>kotlin-stdlib</artifactId>
+        </dependency>
         <dependency>
             <groupId>com.vladsch.flexmark</groupId>
             <artifactId>flexmark-util-misc</artifactId>
@@ -28,4 +32,14 @@
             <version>24.0.1</version>
         </dependency>
     </dependencies>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.jetbrains.kotlin</groupId>
+                <artifactId>kotlin-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+
+    </build>
+
 </project>

flexmark-util-data/src/main/java/com/vladsch/flexmark/util/data/DataKeyDelegate.kt

@@ -0,0 +1,16 @@
+package com.vladsch.flexmark.util.data
+
+import kotlin.reflect.KProperty
+
+@JvmInline
+value class DataKeyDelegate<T : Any>(private val key: DataKey<T>) {
+
+    operator fun setValue(thisRef: MutableDataHolder, property: KProperty<*>, value: T) {
+        key.set(thisRef, value)
+    }
+
+    operator fun getValue(thisRef: MutableDataHolder, property: KProperty<*>): T =
+        key.get(thisRef)
+}
+
+fun <T : Any> key(key: DataKey<T>) = DataKeyDelegate(key)

flexmark-util-data/src/main/java/com/vladsch/flexmark/util/data/ExtensionDelegates.kt

@@ -0,0 +1,4 @@
+package com.vladsch.flexmark.util.data
+
+import com.vladsch.flexmark.util.misc.Extension
+

flexmark-util-data/src/main/java/com/vladsch/flexmark/util/data/NullableDataKeyDelegate.kt

@@ -0,0 +1,13 @@
+package com.vladsch.flexmark.util.data
+
+import kotlin.reflect.KProperty
+
+@JvmInline
+value class NullableDataKeyDelegate<T : Any>(private val key: NullableDataKey<T>) {
+    operator fun setValue(thisRef: MutableDataHolder, property: KProperty<*>, value: T) {
+        key.set(thisRef, value)
+    }
+
+    operator fun getValue(thisRef: MutableDataHolder, property: KProperty<*>): T? =
+        key.get(thisRef)
+}

flexmark-util-data/src/main/java/com/vladsch/flexmark/util/data/SharedDataKeys.kt

@@ -0,0 +1,41 @@
+package com.vladsch.flexmark.util.data
+
+import com.vladsch.flexmark.util.misc.Extension
+
+fun MutableDataHolder.addExtensions(vararg extensions: Extension) {
+    this.extensions += listOf(*extensions)
+}
+
+var MutableDataHolder.extensions: Collection<Extension> by key(SharedDataKeys.EXTENSIONS)
+var MutableDataHolder.headingNoAtxSpace: Boolean by key(SharedDataKeys.HEADING_NO_ATX_SPACE)
+var MutableDataHolder.escapeHeadingNoAtxSpace: Boolean by key(SharedDataKeys.ESCAPE_HEADING_NO_ATX_SPACE)
+var MutableDataHolder.htmlForTranslator: Boolean by key(SharedDataKeys.HTML_FOR_TRANSLATOR)
+var MutableDataHolder.intellijDummyIdentifier: Boolean by key(SharedDataKeys.INTELLIJ_DUMMY_IDENTIFIER)
+var MutableDataHolder.parseInnerHtmlComments: Boolean by key(SharedDataKeys.PARSE_INNER_HTML_COMMENTS)
+var MutableDataHolder.blankLinesInAst: Boolean by key(SharedDataKeys.BLANK_LINES_IN_AST)
+var MutableDataHolder.translationHtmlBlockTagPattern: String by key(SharedDataKeys.TRANSLATION_HTML_BLOCK_TAG_PATTERN)
+var MutableDataHolder.translationHtmlInlineTagPattern: String by key(SharedDataKeys.TRANSLATION_HTML_INLINE_TAG_PATTERN)
+var MutableDataHolder.translationAutolinkTagPattern: String by key(SharedDataKeys.TRANSLATION_AUTOLINK_TAG_PATTERN)
+var MutableDataHolder.rendererMaxTrailingBlankLines: Int by key(SharedDataKeys.RENDERER_MAX_TRAILING_BLANK_LINES)
+var MutableDataHolder.rendererMaxBlankLines: Int by key(SharedDataKeys.RENDERER_MAX_BLANK_LINES)
+var MutableDataHolder.indentSize: Int by key(SharedDataKeys.INDENT_SIZE)
+var MutableDataHolder.percentEncodeUrls: Boolean by key(SharedDataKeys.PERCENT_ENCODE_URLS)
+var MutableDataHolder.headerIdGeneratorResolveDupes: Boolean by key(SharedDataKeys.HEADER_ID_GENERATOR_RESOLVE_DUPES)
+var MutableDataHolder.headerIdGeneratorToDashChars: String by key(SharedDataKeys.HEADER_ID_GENERATOR_TO_DASH_CHARS)
+var MutableDataHolder.headerIdGeneratorNonDashChars: String by key(SharedDataKeys.HEADER_ID_GENERATOR_NON_DASH_CHARS)
+var MutableDataHolder.headerIdGeneratorNoDupedDashes: Boolean by key(SharedDataKeys.HEADER_ID_GENERATOR_NO_DUPED_DASHES)
+var MutableDataHolder.headerIdGeneratorNonAsciiToLowercase: Boolean by key(SharedDataKeys.HEADER_ID_GENERATOR_NON_ASCII_TO_LOWERCASE)
+var MutableDataHolder.headerIdRefTextTrimLeadingSpaces: Boolean by key(SharedDataKeys.HEADER_ID_REF_TEXT_TRIM_LEADING_SPACES)
+var MutableDataHolder.headerIdRefTextTrimTrailingSpaces: Boolean by key(SharedDataKeys.HEADER_ID_REF_TEXT_TRIM_TRAILING_SPACES)
+var MutableDataHolder.headerIdAddEmojiShortcut: Boolean by key(SharedDataKeys.HEADER_ID_ADD_EMOJI_SHORTCUT)
+var MutableDataHolder.renderHeaderId: Boolean by key(SharedDataKeys.RENDER_HEADER_ID)
+var MutableDataHolder.generateHeaderId: Boolean by key(SharedDataKeys.GENERATE_HEADER_ID)
+var MutableDataHolder.doNotRenderLinks: Boolean by key(SharedDataKeys.DO_NOT_RENDER_LINKS)
+var MutableDataHolder.formatterMaxBlankLines: Int by key(SharedDataKeys.FORMATTER_MAX_BLANK_LINES)
+var MutableDataHolder.formatterMaxTrailingBlankLines: Int by key(SharedDataKeys.FORMATTER_MAX_TRAILING_BLANK_LINES)
+var MutableDataHolder.blockQuoteBlankLines: Boolean by key(SharedDataKeys.BLOCK_QUOTE_BLANK_LINES)
+var MutableDataHolder.applySpecialLeadInHandlers: Boolean by key(SharedDataKeys.APPLY_SPECIAL_LEAD_IN_HANDLERS)
+var MutableDataHolder.escapeSpecialChars: Boolean by key(SharedDataKeys.ESCAPE_SPECIAL_CHARS)
+var MutableDataHolder.escapeNumberedLeadIn: Boolean by key(SharedDataKeys.ESCAPE_NUMBERED_LEAD_IN)
+var MutableDataHolder.unescapeSpecialChars: Boolean by key(SharedDataKeys.UNESCAPE_SPECIAL_CHARS)
+var MutableDataHolder.runningTests: Boolean by key(SharedDataKeys.RUNNING_TESTS)

pom.xml

@@ -89,6 +89,7 @@
         <flexmark.javadoc.location>${project.basedir}/target/apidocs/</flexmark.javadoc.location>
         <!-- Don't automatically publish artifacts to Central, we might want to inspect them first. -->
         <nexus.staging.autoRelease>false</nexus.staging.autoRelease>
+        <kotlin.version>1.9.10</kotlin.version>
     </properties>
 
     <distributionManagement>
@@ -136,6 +137,27 @@
                         </descriptors>
                     </configuration>
                 </plugin>
+                <plugin>
+                    <groupId>org.jetbrains.kotlin</groupId>
+                    <artifactId>kotlin-maven-plugin</artifactId>
+                    <version>${kotlin.version}</version>
+
+                    <executions>
+                        <execution>
+                            <id>compile</id>
+                            <goals>
+                                <goal>compile</goal>
+                            </goals>
+                        </execution>
+
+                        <execution>
+                            <id>test-compile</id>
+                            <goals>
+                                <goal>test-compile</goal>
+                            </goals>
+                        </execution>
+                    </executions>
+                </plugin>
             </plugins>
         </pluginManagement>
     </build>
@@ -534,6 +556,13 @@
                 <version>${project.version}</version>
             </dependency>
 
+            <!--  Kotlin runtime dependencies -->
+            <dependency>
+                <groupId>org.jetbrains.kotlin</groupId>
+                <artifactId>kotlin-stdlib</artifactId>
+                <version>${kotlin.version}</version>
+            </dependency>
+
             <!-- Common test dependencies -->
             <dependency>
                 <groupId>junit</groupId>