interface-inheritance-problem.php

<?php

/**
 * Marker interface
 */
interface IConfig {}

/**
 * An api sdk tool
 */
interface IApi
{
    public __construct(IConfig $cfg);
}

/**
 * Api configuration specific to http
 */
interface IHttpConfig extends IConfig
{
    public getSomeNiceHttpSpecificFeature();
}

/**
 * Illegal, but would be really nice to have. Is there a good reason this is not allowed?
 */
interface IHttpApi extends IApi
{
    public __construct(IHttpConfig $cfg);
}