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|
=================================================================
Logtalk - Object oriented extension to Prolog
Release 2.27.1
Copyright (c) 1998-2006 Paulo Moura. All Rights Reserved.
=================================================================
% start by loading the example:
| ?- logtalk_load(dcgs(loader)).
...
% DCG rules implementing a simple calculator:
| ?- calculator::parse("1+2-3*4", Result).
Result = -9
yes
% solve a cellphone keypad encoded enigma:
| ?- enigma::solve("4 96853 5683 86 4283 346637 9484 968 8664448", Message).
Message = [i, would, love, to, have, dinner, with, you, tonight]
yes
% recognizing gramatically correct sentences:
| ?- sentence::parse([the, girl, likes, the, boy], Result).
Result = true
yes
| ?- sentence::parse([the, girl, scares, the, boy], Result).
Result = false
yes
% generating parse trees for sentences:
| ?- parsetree::parse([the, girl, likes, the, boy], Tree).
Tree = s(np(d(the), n(girl)), vp(v(likes), np(d(the), n(boy))))
yes
% bill of materials example:
| ?- bom::parts(bike, L).
L = [frame, crank, pedal, pedal, chain, spokes, rim, hub, spokes, rim, hub]
yes
| ?- bom::parts(wheel, L).
L = [spokes, rim, hub]
yes
% parsing command-line shell input:
| ?- shell::parse("pwd; cd ..; ls -a", L).
L = [pwd,'cd ..','ls -a'] ?
yes
% convert a string to a list of tokens (words, numbers, ponctuation):
| ?- tokenizer::tokens(" We owe $1,048,576.24 to Agent 007 for Version 3.14159! ", Tokens).
Tokens = [we,owe,$,1048576.24,to,agent,7,for,version,3.14159,!] ?
yes
% walker movements:
| ?- walker::walk([n(5), e(4), s(2), nw(8), s(5), se(1), n(4)], Ending).
Ending = -0.94974746830583223,6.9497474683058318 ?
yes
% conversion between compound terms and XML:
| ?- xml::convert(word(child, children), word(singular, plural), XML).
XML = '<word><singular>child</singular><plural>children</plural></word>'
yes
| ?- xml::convert(Term, Interpretation, '<word><singular>child</singular><plural>children</plural></word>').
Term = word(child, children)
Interpretation = word(singular, plural)
yes
% parsing URLs:
| ?- url::parse("http://www.logtalk.org", Components).
Components = [protocol(http), address([www, logtalk, org]), path([]), file('')]
yes
| ?- url::parse("http://www.logtalk.org/", Components).
Components = [protocol(http), address([www, logtalk, org]), path(['']), file('')]
yes
| ?- url::parse("http://www.logtalk.org/cvs", Components).
Components = [protocol(http), address([www, logtalk, org]), path([cvs]), file('')]
yes
| ?- url::parse("http://www.logtalk.org/cvs.html", Components).
Components = [protocol(http), address([www, logtalk, org]), path([]), file('cvs.html')]
yes
| ?- url::parse("http://193.136.64.5/files/update", Components).
Components = [protocol(http), address([193, 136, 64, 5]), path([files, update]), file('')]
yes
% command language example:
| ?- faa::main.
Fly Amzi! Air
enter command> list flights
aa101
aa102
aa103
enter command> book elana aa102
enter command> book tom aa102
enter command> list passengers aa102
elana
tom
enter command> exit
yes
% double bypass using the {}/1 control constructs of grammar rules and Logtalk:
| ?- bypass::phrase(foo, _, _).
bar predicate called
yes
% run the Logtalk DCG translator on the test cases:
| ?- dcgtest::run.
...
|
