ezy_dll_test

This sample program demonstrates how to use external DLL inside EZY Prolog code.

It simply passes string to Visual Prolog DLL which returns modified string.

/* EZY PROLOG. Copyright (C) 1997-2013 EDMGROUP (Australia)
http://www.ezy-software.com
Written by: Serguei Penkov
email: ezy-soft@ezy-software.com
DLL Sources in:
SourceSamples\EZY_DLL_Test directory

EZY PROLOG PROGRAM calls external DLL, written in Visual Prolog 5.2
This DLL simply receives facts from EZY Prolog and asserts them into database,
declared inside DLL. To do so, EZY Prolog calls dll_assert function
EZY Prolog program can get all facts from dll by calling dll_findall
This function call returns list of facts inside a string.
Use term_str to convert string into list of facts
EZY Prolog program can retrieve facts non-deterministically by calling dll_retract
Non-determinism is provided by EZY Prolog. DLL function simply returns (0) to inform
EZY Prolog that all facts has been processed.

For Cucstom Control handling in DLL - please open EZY FORM:
Samples\ezy_dll_custom_control.ezy

*/

domains
my_complex_domain = complex(STRING NAME, SLIST PARAMS)
my_complex_domain_list = my_complex_domain*

predicates
    prolog_main
    dll_subsystem_test(STRING DLL_NAME)

clauses

prolog_main():-
    write("Welcome to EZY Prolog\nDLL Subsystem testing\n"),
    DLL_NAME = "ezy_dll_test.dll",
    syspath(EXEPATH,_),
    format(DLL_FULL_NAME,"%s%s",EXEPATH,DLL_NAME),
    STR_IN = "This is string from EZY Prolog",
    ezy_dll_call(DLL_FULL_NAME,"dll_function_test",STR_IN,STR_OUT),
    write("Results from DLL:\nSTR_IN=",STR_IN,"\nSTR_OUT=",STR_OUT),nl,
    dll_subsystem_test(DLL_FULL_NAME),
    !.

dll_subsystem_test(DLL_NAME):-
    write("Start of EZY DLL test. DLL_NAME=",DLL_NAME),nl,
    fail.

dll_subsystem_test(DLL_NAME):-
    % ASSET FACTS INSIDE DLL
    % USER TERM_STR TO CREATE INPUT PARAMETER FOR DLL
    CALL_NAME = "dll_assert",
    MY_FACT1 = complex("Bob",["Prolog","Java","Cobol"]),
    term_str(my_complex_domain,MY_FACT1,MY_FACT_STR1),
    ezy_dll_call(DLL_NAME,CALL_NAME,MY_FACT_STR1,RC1),
    write("Asserting First fact:\n\t",MY_FACT1,"\n\tRC=",RC1),nl,
    MY_FACT2 = complex("Tony",["Beer","Wine","Visual Basic"]),
    term_str(my_complex_domain,MY_FACT2,MY_FACT_STR2),
    ezy_dll_call(DLL_NAME,CALL_NAME,MY_FACT_STR2,RC2),
    write("Asserting Second fact:\n\t",MY_FACT2,"\n\tRC=",RC2),nl,
    fail.
dll_subsystem_test(DLL_NAME):-
    write("Test for findall in DLL - get list of facts:\n\tNote: list should have 2 facts, asserted before\n"),
    CALL_NAME = "dll_findall",
    ezy_dll_call(DLL_NAME,CALL_NAME,"",RESULT_STR),
    term_str(my_complex_domain_list,FACT_LIST,RESULT_STR),
    % now we have LIST OF FACTS
    write("findall test\n\tstring to my_complex_domain_list conversion =\n\t",FACT_LIST),nl,
    fail.
dll_subsystem_test(DLL_NAME):-
    % NOW - SIMULATE NON-DETERMINISTIC RETRIEVAL OF FACTS FROM DLL
    % NOTE - ezy_dll_call will fail when no facts found in the DLL
    write("Retract facts non-deterministically:\n"),
    CALL_NAME = "dll_retract",
    ezy_dll_call_nondeterm(DLL_NAME,CALL_NAME,"",RESULT_STR),
    term_str(my_complex_domain_list,MY_FACT,RESULT_STR),
    write("Fact retracted\n\tstring to my_complex_domain_list conversion =\n\t",MY_FACT),nl,
    fail.
dll_subsystem_test(DLL_NAME):-
    write("End of EZY DLL test. DLL_NAME=",DLL_NAME),nl.

goal
    prolog_main().

/* PROGRAM OUTPUT */

EZY Prolog. Copyright (C) 1997-2006 EDMGROUP (Australia)
http://www.ezy-software.com
Check PDC Prolog compatibility
Program verification completed

Program compiled
Welcome to EZY Prolog
DLL Subsystem testing
Results from DLL:
STR_IN=This is string from EZY Prolog
STR_OUT=Updated string from DLL: This is string from EZY Prolog
Start of EZY DLL test. DLL_NAME=C:Program\ FilesEZY\-SoftwareEZY_Prolog_Suite\ezy_dll_test\.dll
Asserting First fact:
    complex("Bob",["Prolog","Java","Cobol"])
    RC=OK
Asserting Second fact:
    complex("Tony",["Beer","Wine","Visual Basic"])
    RC=OK
Test for findall in DLL - get list of facts :
    Note: list should have 2 facts , asserted before
findall test
    string to my_complex_domain_list conversion =
    [[complex("Bob","Prolog","Java","Cobol")],complex("Tony","Beer","Wine","Visual Basic")]
Retract facts non-deterministically:
Fact retracted
    string to my_complex_domain_list conversion =
    complex("Bob",["Prolog","Java","Cobol"])
Fact retracted
    string to my_complex_domain_list conversion =
    complex("Tony",["Beer","Wine","Visual Basic"])
End of EZY DLL test.
DLL_NAME=C:Program\ FilesEZY\-SoftwareEZY_Prolog_Suite\ezy_dll_test\.dll