diff --git a/src/main/java/com/plugatar/jkscope/JKScope.java b/src/main/java/com/plugatar/jkscope/JKScope.java
index 8360987..df14410 100644
--- a/src/main/java/com/plugatar/jkscope/JKScope.java
+++ b/src/main/java/com/plugatar/jkscope/JKScope.java
@@ -34,6 +34,9 @@
 import com.plugatar.jkscope.function.ThPredicate;
 import com.plugatar.jkscope.function.ThRunnable;
 import com.plugatar.jkscope.function.ThSupplier;
+import com.plugatar.jkscope.function.ThToDoubleFunction;
+import com.plugatar.jkscope.function.ThToIntFunction;
+import com.plugatar.jkscope.function.ThToLongFunction;
 import com.plugatar.jkscope.function.ThTriConsumer;
 import com.plugatar.jkscope.function.ThTriFunction;
 
@@ -95,6 +98,9 @@
  * <li>{@link #letLongRec(long, ThLongObjToLongFunction)}</li>
  * <li>{@link #letDoubleRec(double, ThDoubleObjToDoubleFunction)}</li>
  * <li>{@link #letWith(Object, ThFunction)}</li>
+ * <li>{@link #letIntWith(Object, ThToIntFunction)}</li>
+ * <li>{@link #letLongWith(Object, ThToLongFunction)}</li>
+ * <li>{@link #letDoubleWith(Object, ThToDoubleFunction)}</li>
  * <li>{@link #letWithResource(AutoCloseable, ThFunction)}</li>
  * <li>{@link #letWith(Object, Object, ThBiFunction)}</li>
  * <li>{@link #letWith(Object, Object, Object, ThTriFunction)}</li>
@@ -665,6 +671,66 @@ static <V, R> R letWith(final V value,
     return block.asUnchecked().apply(value);
   }
 
+  /**
+   * Performs given function block on given value and returns result.
+   * <pre>{@code
+   * int value = letWith("1234", it -> {
+   *   System.out.println(it);
+   *   return Integer.parseInt(it);
+   * });
+   * }</pre>
+   *
+   * @param value the value
+   * @param block the function block
+   * @param <V>   the type of the value
+   * @return result
+   */
+  static <V> int letIntWith(final V value,
+                            final ThToIntFunction<? super V, ?> block) {
+    blockArgNotNull(block);
+    return block.asUnchecked().apply(value);
+  }
+
+  /**
+   * Performs given function block on given value and returns result.
+   * <pre>{@code
+   * long value = letWith("1234", it -> {
+   *   System.out.println(it);
+   *   return Long.parseLong(it);
+   * });
+   * }</pre>
+   *
+   * @param value the value
+   * @param block the function block
+   * @param <V>   the type of the value
+   * @return result
+   */
+  static <V> long letLongWith(final V value,
+                              final ThToLongFunction<? super V, ?> block) {
+    blockArgNotNull(block);
+    return block.asUnchecked().apply(value);
+  }
+
+  /**
+   * Performs given function block on given value and returns result.
+   * <pre>{@code
+   * double value = letWith("1234.0", it -> {
+   *   System.out.println(it);
+   *   return Double.parseLong(it);
+   * });
+   * }</pre>
+   *
+   * @param value the value
+   * @param block the function block
+   * @param <V>   the type of the value
+   * @return result
+   */
+  static <V> double letDoubleWith(final V value,
+                                  final ThToDoubleFunction<? super V, ?> block) {
+    blockArgNotNull(block);
+    return block.asUnchecked().apply(value);
+  }
+
   /**
    * Performs given function block on {@link AutoCloseable} value, close this value and returns result.
    * <pre>{@code
diff --git a/src/main/java/com/plugatar/jkscope/function/ThToDoubleFunction.java b/src/main/java/com/plugatar/jkscope/function/ThToDoubleFunction.java
new file mode 100644
index 0000000..1bf7b44
--- /dev/null
+++ b/src/main/java/com/plugatar/jkscope/function/ThToDoubleFunction.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2024 Evgenii Plugatar
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.plugatar.jkscope.function;
+
+/**
+ * The {@link java.util.function.Function} specialization that produces a {@code double}-valued result and might throw
+ * an exception
+ *
+ * @param <T> the type of the input argument
+ * @param <E> the type of the throwing exception
+ * @see java.util.function.Function
+ */
+@FunctionalInterface
+public interface ThToDoubleFunction<T, E extends Throwable> {
+
+  /**
+   * Applies this function to the given argument.
+   *
+   * @param t the input argument
+   * @return result
+   * @throws E if function threw exception
+   */
+  double apply(T t) throws E;
+
+  /**
+   * Returns this functions as an unchecked functions.
+   *
+   * @return unchecked function
+   */
+  @SuppressWarnings("unchecked")
+  default ThToDoubleFunction<T, RuntimeException> asUnchecked() {
+    return (ThToDoubleFunction<T, RuntimeException>) this;
+  }
+}
diff --git a/src/main/java/com/plugatar/jkscope/function/ThToIntFunction.java b/src/main/java/com/plugatar/jkscope/function/ThToIntFunction.java
new file mode 100644
index 0000000..772eca8
--- /dev/null
+++ b/src/main/java/com/plugatar/jkscope/function/ThToIntFunction.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2024 Evgenii Plugatar
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.plugatar.jkscope.function;
+
+/**
+ * The {@link java.util.function.Function} specialization that produces an {@code int}-valued result and might throw an
+ * exception
+ *
+ * @param <T> the type of the input argument
+ * @param <E> the type of the throwing exception
+ * @see java.util.function.Function
+ */
+@FunctionalInterface
+public interface ThToIntFunction<T, E extends Throwable> {
+
+  /**
+   * Applies this function to the given argument.
+   *
+   * @param t the input argument
+   * @return result
+   * @throws E if function threw exception
+   */
+  int apply(T t) throws E;
+
+  /**
+   * Returns this functions as an unchecked functions.
+   *
+   * @return unchecked function
+   */
+  @SuppressWarnings("unchecked")
+  default ThToIntFunction<T, RuntimeException> asUnchecked() {
+    return (ThToIntFunction<T, RuntimeException>) this;
+  }
+}
diff --git a/src/main/java/com/plugatar/jkscope/function/ThToLongFunction.java b/src/main/java/com/plugatar/jkscope/function/ThToLongFunction.java
new file mode 100644
index 0000000..65e1c01
--- /dev/null
+++ b/src/main/java/com/plugatar/jkscope/function/ThToLongFunction.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2024 Evgenii Plugatar
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.plugatar.jkscope.function;
+
+/**
+ * The {@link java.util.function.Function} specialization that produces a {@code long}-valued result and might throw an
+ * exception
+ *
+ * @param <T> the type of the input argument
+ * @param <E> the type of the throwing exception
+ * @see java.util.function.Function
+ */
+@FunctionalInterface
+public interface ThToLongFunction<T, E extends Throwable> {
+
+  /**
+   * Applies this function to the given argument.
+   *
+   * @param t the input argument
+   * @return result
+   * @throws E if function threw exception
+   */
+  long apply(T t) throws E;
+
+  /**
+   * Returns this functions as an unchecked functions.
+   *
+   * @return unchecked function
+   */
+  @SuppressWarnings("unchecked")
+  default ThToLongFunction<T, RuntimeException> asUnchecked() {
+    return (ThToLongFunction<T, RuntimeException>) this;
+  }
+}
diff --git a/src/test/java/com/plugatar/jkscope/JKScopeTest.java b/src/test/java/com/plugatar/jkscope/JKScopeTest.java
index ebf769d..f758b64 100644
--- a/src/test/java/com/plugatar/jkscope/JKScopeTest.java
+++ b/src/test/java/com/plugatar/jkscope/JKScopeTest.java
@@ -34,6 +34,9 @@
 import com.plugatar.jkscope.function.ThPredicate;
 import com.plugatar.jkscope.function.ThRunnable;
 import com.plugatar.jkscope.function.ThSupplier;
+import com.plugatar.jkscope.function.ThToDoubleFunction;
+import com.plugatar.jkscope.function.ThToIntFunction;
+import com.plugatar.jkscope.function.ThToLongFunction;
 import com.plugatar.jkscope.function.ThTriConsumer;
 import com.plugatar.jkscope.function.ThTriFunction;
 import org.junit.jupiter.api.Test;
@@ -470,6 +473,33 @@ void letWithStaticMethodThrowsNPEForNullArg() {
       .isInstanceOf(NullPointerException.class);
   }
 
+  @Test
+  void letIntWithStaticMethodThrowsNPEForNullArg() {
+    final Object value = new Object();
+    final ThToIntFunction<Object, Throwable> block = null;
+
+    assertThatThrownBy(() -> JKScope.letIntWith(value, block))
+      .isInstanceOf(NullPointerException.class);
+  }
+
+  @Test
+  void letLongWithStaticMethodThrowsNPEForNullArg() {
+    final Object value = new Object();
+    final ThToLongFunction<Object, Throwable> block = null;
+
+    assertThatThrownBy(() -> JKScope.letLongWith(value, block))
+      .isInstanceOf(NullPointerException.class);
+  }
+
+  @Test
+  void letDoubleWithStaticMethodThrowsNPEForNullArg() {
+    final Object value = new Object();
+    final ThToDoubleFunction<Object, Throwable> block = null;
+
+    assertThatThrownBy(() -> JKScope.letDoubleWith(value, block))
+      .isInstanceOf(NullPointerException.class);
+  }
+
   @Test
   void letWithResourceMethodThrowsNPEForNullArg() {
     final AutoCloseable value = new AutoCloseableImpl();
@@ -1105,6 +1135,84 @@ void letWithStaticMethodThrowsException() {
       .isSameAs(throwable);
   }
 
+  @Test
+  void letIntWithStaticMethod() {
+    final Object value = new Object();
+    final int result = 111;
+    final AtomicReference<Object> valueRef = new AtomicReference<>();
+    final ThToIntFunction<Object, Throwable> block = arg -> {
+      valueRef.set(arg);
+      return result;
+    };
+
+    assertThat(JKScope.letIntWith(value, block))
+      .isEqualTo(result);
+    assertThat(valueRef.get())
+      .isSameAs(value);
+  }
+
+  @Test
+  void letIntWithStaticMethodThrowsException() {
+    final Object value = new Object();
+    final Throwable throwable = new Throwable();
+    final ThToIntFunction<Object, Throwable> block = arg -> { throw throwable; };
+
+    assertThatThrownBy(() -> JKScope.letIntWith(value, block))
+      .isSameAs(throwable);
+  }
+
+  @Test
+  void letLongWithStaticMethod() {
+    final Object value = new Object();
+    final long result = 111L;
+    final AtomicReference<Object> valueRef = new AtomicReference<>();
+    final ThToLongFunction<Object, Throwable> block = arg -> {
+      valueRef.set(arg);
+      return result;
+    };
+
+    assertThat(JKScope.letLongWith(value, block))
+      .isEqualTo(result);
+    assertThat(valueRef.get())
+      .isSameAs(value);
+  }
+
+  @Test
+  void letLongWithStaticMethodThrowsException() {
+    final Object value = new Object();
+    final Throwable throwable = new Throwable();
+    final ThToLongFunction<Object, Throwable> block = arg -> { throw throwable; };
+
+    assertThatThrownBy(() -> JKScope.letLongWith(value, block))
+      .isSameAs(throwable);
+  }
+
+  @Test
+  void letDoubleWithStaticMethod() {
+    final Object value = new Object();
+    final double result = 111.0;
+    final AtomicReference<Object> valueRef = new AtomicReference<>();
+    final ThToDoubleFunction<Object, Throwable> block = arg -> {
+      valueRef.set(arg);
+      return result;
+    };
+
+    assertThat(JKScope.letDoubleWith(value, block))
+      .isEqualTo(result);
+    assertThat(valueRef.get())
+      .isSameAs(value);
+  }
+
+  @Test
+  void letDoubleWithStaticMethodThrowsException() {
+    final Object value = new Object();
+    final Throwable throwable = new Throwable();
+    final ThToDoubleFunction<Object, Throwable> block = arg -> { throw throwable; };
+
+    assertThatThrownBy(() -> JKScope.letDoubleWith(value, block))
+      .isSameAs(throwable);
+  }
+
   @Test
   void letWithResourceMethod() {
     final AutoCloseableImpl value = new AutoCloseableImpl();
diff --git a/src/test/java/com/plugatar/jkscope/function/ThToDoubleFunctionTest.java b/src/test/java/com/plugatar/jkscope/function/ThToDoubleFunctionTest.java
new file mode 100644
index 0000000..8681fda
--- /dev/null
+++ b/src/test/java/com/plugatar/jkscope/function/ThToDoubleFunctionTest.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2024 Evgenii Plugatar
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.plugatar.jkscope.function;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.concurrent.atomic.AtomicReference;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+/**
+ * Tests for {@link ThToDoubleFunction}.
+ */
+final class ThToDoubleFunctionTest {
+
+  @Test
+  void asUncheckedMethod() {
+    final Object value = new Object();
+    final AtomicReference<Object> valueRef = new AtomicReference<>();
+    final double result = 111.0;
+    final ThToDoubleFunction<Object, Throwable> origin = arg -> {
+      valueRef.set(arg);
+      return result;
+    };
+
+    final ThToDoubleFunction<Object, RuntimeException> unchecked = origin.asUnchecked();
+    assertThat(unchecked.apply(value))
+      .isEqualTo(result);
+    assertThat(valueRef.get())
+      .isSameAs(value);
+  }
+
+  @Test
+  void asUncheckedMethodThrowsException() {
+    final Object value = new Object();
+    final Throwable throwable = new Throwable();
+    final ThToDoubleFunction<Object, Throwable> origin = arg -> { throw throwable; };
+
+    final ThToDoubleFunction<Object, RuntimeException> unchecked = origin.asUnchecked();
+    assertThatThrownBy(() -> unchecked.apply(value))
+      .isSameAs(throwable);
+  }
+}
diff --git a/src/test/java/com/plugatar/jkscope/function/ThToIntFunctionTest.java b/src/test/java/com/plugatar/jkscope/function/ThToIntFunctionTest.java
new file mode 100644
index 0000000..03566a9
--- /dev/null
+++ b/src/test/java/com/plugatar/jkscope/function/ThToIntFunctionTest.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2024 Evgenii Plugatar
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.plugatar.jkscope.function;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.concurrent.atomic.AtomicReference;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+/**
+ * Tests for {@link ThToIntFunction}.
+ */
+final class ThToIntFunctionTest {
+
+  @Test
+  void asUncheckedMethod() {
+    final Object value = new Object();
+    final AtomicReference<Object> valueRef = new AtomicReference<>();
+    final int result = 111;
+    final ThToIntFunction<Object, Throwable> origin = arg -> {
+      valueRef.set(arg);
+      return result;
+    };
+
+    final ThToIntFunction<Object, RuntimeException> unchecked = origin.asUnchecked();
+    assertThat(unchecked.apply(value))
+      .isEqualTo(result);
+    assertThat(valueRef.get())
+      .isSameAs(value);
+  }
+
+  @Test
+  void asUncheckedMethodThrowsException() {
+    final Object value = new Object();
+    final Throwable throwable = new Throwable();
+    final ThToIntFunction<Object, Throwable> origin = arg -> { throw throwable; };
+
+    final ThToIntFunction<Object, RuntimeException> unchecked = origin.asUnchecked();
+    assertThatThrownBy(() -> unchecked.apply(value))
+      .isSameAs(throwable);
+  }
+}
diff --git a/src/test/java/com/plugatar/jkscope/function/ThToLongFunctionTest.java b/src/test/java/com/plugatar/jkscope/function/ThToLongFunctionTest.java
new file mode 100644
index 0000000..2eb6770
--- /dev/null
+++ b/src/test/java/com/plugatar/jkscope/function/ThToLongFunctionTest.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2024 Evgenii Plugatar
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.plugatar.jkscope.function;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.concurrent.atomic.AtomicReference;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+/**
+ * Tests for {@link ThToLongFunction}.
+ */
+final class ThToLongFunctionTest {
+
+  @Test
+  void asUncheckedMethod() {
+    final Object value = new Object();
+    final AtomicReference<Object> valueRef = new AtomicReference<>();
+    final long result = 111L;
+    final ThToLongFunction<Object, Throwable> origin = arg -> {
+      valueRef.set(arg);
+      return result;
+    };
+
+    final ThToLongFunction<Object, RuntimeException> unchecked = origin.asUnchecked();
+    assertThat(unchecked.apply(value))
+      .isEqualTo(result);
+    assertThat(valueRef.get())
+      .isSameAs(value);
+  }
+
+  @Test
+  void asUncheckedMethodThrowsException() {
+    final Object value = new Object();
+    final Throwable throwable = new Throwable();
+    final ThToLongFunction<Object, Throwable> origin = arg -> { throw throwable; };
+
+    final ThToLongFunction<Object, RuntimeException> unchecked = origin.asUnchecked();
+    assertThatThrownBy(() -> unchecked.apply(value))
+      .isSameAs(throwable);
+  }
+}