public static <R> IntFunction<R> intFunction(CheckedIntFunction<R> function) {
        return intFunction(function, THROWABLE_TO_RUNTIME_EXCEPTION);
    }
Wrap a {@link CheckedIntFunction} in a {@link IntFunction}.
<p>
Example:
<pre><code>
IntStream.of(1, 2, 3).mapToObj(Unchecked.intFunction(i -> {
    if (i &lt; 0)
        throw new Exception("Only positive numbers allowed");

    return "" + i;
});
</code></pre>
jOOL-java-8/src/main/java/org/jooq/lambda/Unchecked.java