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diff --git a/src/main/java/org/apache/commons/lang3/function/FailableDoubleUnaryOperator.java b/src/main/java/org/apache/commons/lang3/function/FailableDoubleUnaryOperator.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 org.apache.commons.lang3.function;
+
+import java.util.Objects;
+import java.util.function.DoubleUnaryOperator;
+
+/**
+ * A functional interface like {@link DoubleUnaryOperator} that declares a {@link Throwable}.
+ *
+ * @param <E> The kind of thrown exception or error.
+ * @since 3.11
+ */
+public interface FailableDoubleUnaryOperator<E extends Throwable> {
+
+    /** NOP singleton */
+    @SuppressWarnings("rawtypes")
+    FailableDoubleUnaryOperator NOP = t -> 0d;
+
+    /**
+     * Returns a unary operator that always returns its input argument.
+     *
+     * @param <E> The kind of thrown exception or error.
+     * @return a unary operator that always returns its input argument
+     */
+    static <E extends Throwable> FailableDoubleUnaryOperator<E> identity() {
+        return t -> t;
+    }
+
+    /**
+     * Returns The NOP singleton.
+     *
+     * @param <E> The kind of thrown exception or error.
+     * @return The NOP singleton.
+     */
+    static <E extends Throwable> FailableDoubleUnaryOperator<E> nop() {
+        return NOP;
+    }
+
+    /**
+     * Returns a composed {@link FailableDoubleUnaryOperator} like
+     * {@link DoubleUnaryOperator#andThen(DoubleUnaryOperator)}.
+     *
+     * @param after the operator to apply after this one.
+     * @return a composed {@link FailableDoubleUnaryOperator} like
+     *         {@link DoubleUnaryOperator#andThen(DoubleUnaryOperator)}.
+     * @throws NullPointerException if after is null.
+     * @see #compose(FailableDoubleUnaryOperator)
+     */
+    default FailableDoubleUnaryOperator<E> andThen(final FailableDoubleUnaryOperator<E> after) {
+        Objects.requireNonNull(after);
+        return (final double t) -> after.applyAsDouble(applyAsDouble(t));
+    }
+
+    /**
+     * Applies this operator to the given operand.
+     *
+     * @param operand the operand
+     * @return the operator result
+     * @throws E Thrown when a consumer fails.
+     */
+    double applyAsDouble(double operand) throws E;
+
+    /**
+     * Returns a composed {@link FailableDoubleUnaryOperator} like
+     * {@link DoubleUnaryOperator#compose(DoubleUnaryOperator)}.
+     *
+     * @param before the operator to apply before this one.
+     * @return a composed {@link FailableDoubleUnaryOperator} like
+     *         {@link DoubleUnaryOperator#compose(DoubleUnaryOperator)}.
+     * @throws NullPointerException if before is null.
+     * @see #andThen(FailableDoubleUnaryOperator)
+     */
+    default FailableDoubleUnaryOperator<E> compose(final FailableDoubleUnaryOperator<E> before) {
+        Objects.requireNonNull(before);
+        return (final double v) -> applyAsDouble(before.applyAsDouble(v));
+    }
+}