assertCanMutate();
        CollectionSupplier<T, C> explicitValue = getExplicitValue(defaultValue).absentIgnoringIfNeeded(ignoreAbsent);
        setSupplier(explicitValue.plus(collector.absentIgnoringIfNeeded(ignoreAbsent)));
    }

    @Nullable
    @Override
    public Class<C> getType() {
        return Cast.uncheckedCast(collectionType);
    }

        assertCanMutate();
        MapSupplier<K, V> explicitValue = getExplicitValue(defaultValue).absentIgnoringIfNeeded(ignoreAbsent);
        setSupplier(explicitValue.plus(collector.absentIgnoringIfNeeded(ignoreAbsent)));
    }

    private Configurer getConfigurer() {
        return getConfigurer(false);
    }