A runtime-expression-keyed map of pathItem-shaped definitions (§14, C018). The enclosing Request.callbacks is name-keyed, so callbacks[name][expression] is a PathItem.
Request.callbacks
callbacks[name][expression]
A runtime-expression-keyed map of pathItem-shaped definitions (§14, C018). The enclosing
Request.callbacksis name-keyed, socallbacks[name][expression]is a PathItem.