reactor-core/src/main/java/reactor/core/publisher/Flux.java
public final Flux<T> concatWith(Publisher<? extends T> other) {
		if (this instanceof FluxConcatArray) {
			@SuppressWarnings({ "unchecked" })
			FluxConcatArray<T> fluxConcatArray = (FluxConcatArray<T>) this;

			return fluxConcatArray.concatAdditionalSourceLast(other);
		}
		return concat(this, other);
	}
public final Flux<T> concatWith(Publisher<? extends T> other) {
		if (this instanceof FluxConcatArray) {
			@SuppressWarnings({ "unchecked" })
			FluxConcatArray<T> fluxConcatArray = (FluxConcatArray<T>) this;

			return fluxConcatArray.concatAdditionalSourceLast(other);
		}
		return concat(this, other);
	}
Concatenate emissions of this {@link Flux} with the provided {@link Publisher} (no interleave).
<p>
<img class="marble" src="doc-files/marbles/concatWithForFlux.svg" alt="">

@param other the {@link Publisher} sequence to concat after this {@link Flux}

@return a concatenated {@link Flux}