Add documentation metadata and overloads for distinct API

core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/distinct.kt

@@ -4,10 +4,13 @@ import org.jetbrains.kotlinx.dataframe.AnyColumnReference
 import org.jetbrains.kotlinx.dataframe.ColumnsSelector
 import org.jetbrains.kotlinx.dataframe.DataFrame
 import org.jetbrains.kotlinx.dataframe.annotations.AccessApiOverload
+import org.jetbrains.kotlinx.dataframe.api.Select.SelectSelectingOptions
 import org.jetbrains.kotlinx.dataframe.columns.ColumnSet
 import org.jetbrains.kotlinx.dataframe.columns.SingleColumn
 import org.jetbrains.kotlinx.dataframe.columns.toColumnSet
+import org.jetbrains.kotlinx.dataframe.documentation.DocumentationUrls
 import org.jetbrains.kotlinx.dataframe.documentation.DslGrammarTemplateColumnsSelectionDsl.DslGrammarTemplate
+import org.jetbrains.kotlinx.dataframe.documentation.ExcludeFromSources
 import org.jetbrains.kotlinx.dataframe.documentation.Indent
 import org.jetbrains.kotlinx.dataframe.exceptions.DuplicateColumnNamesException
 import org.jetbrains.kotlinx.dataframe.impl.columns.DistinctColumnSet
@@ -16,33 +19,92 @@ import kotlin.reflect.KProperty
 
 // region DataFrame
 
+
+/**
+ * ## The Distinct Operation
+ *
+ * It removes duplicated rows based on {@get PHRASE_ENDING}.
+ *
+ * __NOTE:__ The rows in the resulting [DataFrame] are in the same order as they were in the original [DataFrame].
+ *
+ * {@get [DISTINCT_PARAM] @param [columns]
+ * The names of the columns to consider for evaluating distinct rows.}
+ *
+ * @return A new DataFrame containing only distinct rows.
+ *
+ * @see [Selecting Columns][SelectSelectingOptions].
+ * @see {@include [DocumentationUrls.Distinct]}
+ */
+@ExcludeFromSources
+private interface DistinctDocs {
+    interface DISTINCT_PARAM
+}
+
+/**
+ * {@include [DistinctDocs]}
+ * {@set PHRASE_ENDING all columns}.
+ * {@set [DistinctDocs.DISTINCT_PARAM]}
+ */
 public fun <T> DataFrame<T>.distinct(): DataFrame<T> = distinctBy { all() }
 
+/**
+ * {@include [DistinctDocs]}
+ * {@set PHRASE_ENDING the specified columns}.
+ */
 public fun <T, C> DataFrame<T>.distinct(columns: ColumnsSelector<T, C>): DataFrame<T> = select(columns).distinct()
 
+/**
+ * {@include [DistinctDocs]}
+ * {@set PHRASE_ENDING the specified columns}.
+ */
 @AccessApiOverload
 public fun <T> DataFrame<T>.distinct(vararg columns: KProperty<*>): DataFrame<T> =
     distinct {
         val set = columns.toColumnSet()
         set
     }
 
+/**
+ * {@include [DistinctDocs]}
+ * {@set PHRASE_ENDING the specified columns}.
+ */
 public fun <T> DataFrame<T>.distinct(vararg columns: String): DataFrame<T> = distinct { columns.toColumnSet() }
 
+/**
+ * {@include [DistinctDocs]}
+ * {@set PHRASE_ENDING the specified columns}.
+ */
 @AccessApiOverload
 public fun <T> DataFrame<T>.distinct(vararg columns: AnyColumnReference): DataFrame<T> =
     distinct { columns.toColumnSet() }
 
+/**
+ * {@include [DistinctDocs]}
+ * {@set PHRASE_ENDING the specified columns}.
+ */
 @AccessApiOverload
 public fun <T> DataFrame<T>.distinctBy(vararg columns: KProperty<*>): DataFrame<T> =
     distinctBy { columns.toColumnSet() }
 
+/**
+ * {@include [DistinctDocs]}
+ * {@set PHRASE_ENDING the specified columns}.
+ */
 public fun <T> DataFrame<T>.distinctBy(vararg columns: String): DataFrame<T> = distinctBy { columns.toColumnSet() }
 
+/**
+ * {@include [DistinctDocs]}
+ * {@set PHRASE_ENDING the specified columns}.
+ */
 @AccessApiOverload
 public fun <T> DataFrame<T>.distinctBy(vararg columns: AnyColumnReference): DataFrame<T> =
     distinctBy { columns.toColumnSet() }
 
+
+/**
+ * {@include [DistinctDocs]}
+ * {@set PHRASE_ENDING the specified columns}.
+ */
 public fun <T, C> DataFrame<T>.distinctBy(columns: ColumnsSelector<T, C>): DataFrame<T> {
     val cols = get(columns)
     val distinctIndices = indices.distinctBy { i -> cols.map { it[i] } }

core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/documentation/DocumentationUrls.kt

@@ -77,4 +77,7 @@ internal interface DocumentationUrls {
 
     /** [See `remove` on the documentation website.]({@include [Url]}/remove.html) */
     interface Remove
+
+    /** <a href="{@include [Url]}/distinct.html">See `distinct` on the documentation website.</a> */
+    interface Distinct
 }