1.76.2 Send methods

host ->call: name|host_data, unchecked ...

host<->call is used to implement PCE send/get methods in the host language.

It attempts to convert the first argument into a name. This argument is used to find the function in the host language. For all other arguments, the special arguments @receiver, @arg1, ... @arg10 are expanded to their current bindings. No further typechecking is done as this is already done by the send_method that normally invokes this method.

Diagnostics: Fails silently if first argument cannot be converted into a name or the invoked host-language function fails.

See also

- host<-call
- class send_method
- host->send_catch_all

host ->catch_all: name, any|host_data ...

Call function in the host-language. As requested by the argument types, functions will be evaluated by this method. The method host<->catch_all is invoked by the message passing system if there is no method defined, thus

?- message(@prolog, my_nice_little_predicate).

calls my_nice_little_predicate/0, but

?- message(@prolog, protect).

Invokes object->protect. See also host<->call.

host ->initialise: name=name

Create an interface to the host language. This is allowed, but very uncommon. It might be useful to use mixed synchronous and asynchronous interfaces or multiple message channels.