diff --git a/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/Function.kt b/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/Function.kt
index 20ca398d92..d013a7942f 100644
--- a/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/Function.kt
+++ b/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/Function.kt
@@ -73,8 +73,9 @@ class Random(
 class CharLength<T : String?>(
     val expr: Expression<T>
 ) : Function<Int?>(IntegerColumnType()) {
-    override fun toQueryBuilder(queryBuilder: QueryBuilder): Unit =
+    override fun toQueryBuilder(queryBuilder: QueryBuilder) {
         currentDialect.functionProvider.charLength(expr, queryBuilder)
+    }
 }
 
 /**
@@ -106,8 +107,9 @@ class Concat(
     /** Returns the expressions being concatenated. */
     vararg val expr: Expression<*>
 ) : Function<String>(TextColumnType()) {
-    override fun toQueryBuilder(queryBuilder: QueryBuilder): Unit =
+    override fun toQueryBuilder(queryBuilder: QueryBuilder) {
         currentDialect.functionProvider.concat(separator, queryBuilder, expr = expr)
+    }
 }
 
 /**
@@ -123,8 +125,9 @@ class GroupConcat<T : String?>(
     /** Returns the order in which the elements of each group are sorted. */
     vararg val orderBy: Pair<Expression<*>, SortOrder>
 ) : Function<T>(TextColumnType()) {
-    override fun toQueryBuilder(queryBuilder: QueryBuilder): Unit =
+    override fun toQueryBuilder(queryBuilder: QueryBuilder) {
         currentDialect.functionProvider.groupConcat(this, queryBuilder)
+    }
 }
 
 /**
@@ -136,8 +139,9 @@ class Substring<T : String?>(
     /** Returns the length of the substring. */
     val length: Expression<Int>
 ) : Function<T>(TextColumnType()) {
-    override fun toQueryBuilder(queryBuilder: QueryBuilder): Unit =
+    override fun toQueryBuilder(queryBuilder: QueryBuilder) {
         currentDialect.functionProvider.substring(expr, start, length, queryBuilder)
+    }
 }
 
 /**
@@ -350,8 +354,9 @@ sealed class NextVal<T>(
     columnType: IColumnType
 ) : Function<T>(columnType) {
 
-    override fun toQueryBuilder(queryBuilder: QueryBuilder): Unit =
+    override fun toQueryBuilder(queryBuilder: QueryBuilder) {
         currentDialect.functionProvider.nextVal(seq, queryBuilder)
+    }
 
     class IntNextVal(seq: Sequence) : NextVal<Int>(seq, IntegerColumnType())
     class LongNextVal(seq: Sequence) : NextVal<Long>(seq, LongColumnType())
@@ -386,18 +391,20 @@ class CaseWhenElse<T, R : T>(
             ?: caseWhen.cases.map { it.second }.filterIsInstance<ExpressionWithColumnType<*>>().firstOrNull()?.columnType
             ?: BooleanColumnType.INSTANCE
 
-    override fun toQueryBuilder(queryBuilder: QueryBuilder): Unit = queryBuilder {
-        append("CASE ")
-        if (caseWhen.value != null) {
-            +caseWhen.value
-            +" "
-        }
+    override fun toQueryBuilder(queryBuilder: QueryBuilder) {
+        queryBuilder {
+            append("CASE ")
+            if (caseWhen.value != null) {
+                +caseWhen.value
+                +" "
+            }
 
-        for ((first, second) in caseWhen.cases) {
-            append("WHEN ", first, " THEN ", second)
-        }
+            for ((first, second) in caseWhen.cases) {
+                append("WHEN ", first, " THEN ", second)
+            }
 
-        append(" ELSE ", elseResult, " END")
+            append(" ELSE ", elseResult, " END")
+        }
     }
 }
 
@@ -428,6 +435,7 @@ class Cast<T>(
     val expr: Expression<*>,
     columnType: IColumnType
 ) : Function<T>(columnType) {
-    override fun toQueryBuilder(queryBuilder: QueryBuilder): Unit =
+    override fun toQueryBuilder(queryBuilder: QueryBuilder) {
         currentDialect.functionProvider.cast(expr, columnType, queryBuilder)
+    }
 }