URL encoding/decoding

Author(s): The Ciao Development Team.

This module implements URL encoding/decoding predicates.

Usage and interface

Library usage:
:- use_module(library(http/url)).
Exports:
- Predicates:
  url_info/2, url_info_relative/3.
- Regular Types:
  url_term/1.

Documentation on exports

A term specifying an Internet Uniform Resource Locator. Currently only HTTP URLs are supported. Example: http('ciao-lang.org',80,"/ciao/"). Defined as

url_term(http(Hostname,Port,URIStr)) :-
    atm(Hostname),
    int(Port),
    string(URIStr).

Usage:url_term(URL)

URL specifies a URL.

PREDICATEurl_info/2

url_info(URL,URLTerm)

Translates a URL URL to a Prolog structure URLTerm which details its various components, and vice-versa. For now non-HTTP URLs make the predicate fail.

Usage 1:

Call and exit should be compatible with:
(url:url_term/1)URLTerm specifies a URL.
The following properties should hold at call time:
(basic_props:atm/1)URL is an atom.
The following properties should hold upon exit:
(url:url_term/1)URLTerm specifies a URL.

Usage 2:

Call and exit should be compatible with:
(url:url_term/1)URLTerm specifies a URL.
The following properties should hold at call time:
(basic_props:string/1)URL is a string (a list of character codes).
The following properties should hold upon exit:
(url:url_term/1)URLTerm specifies a URL.

Usage 3:

The following properties should hold at call time:
(term_typing:var/1)URL is a free variable.
(url:url_term/1)URLTerm specifies a URL.
The following properties should hold upon exit:
(basic_props:string/1)URL is a string (a list of character codes).

PREDICATEurl_info_relative/3

url_info_relative(URL,BaseURLTerm,URLTerm)

Translates a relative URL URL which appears in the HTML page refered to by BaseURLTerm into URLTerm, a Prolog structure containing its absolute parameters. Absolute URLs are translated as with url_info/2. E.g.

url_info_relative("dadu.html",
              http('www.foo.com',80,"/bar/scoob.html"), Info)

gives Info = http('www.foo.com',80,"/bar/dadu.html").

Usage 1:

Call and exit should be compatible with:
(url:url_term/1)URLTerm specifies a URL.
The following properties should hold at call time:
(basic_props:atm/1)URL is an atom.
(url:url_term/1)BaseURLTerm specifies a URL.
The following properties should hold upon exit:
(url:url_term/1)URLTerm specifies a URL.

Usage 2:

Call and exit should be compatible with:
(url:url_term/1)URLTerm specifies a URL.
The following properties should hold at call time:
(basic_props:string/1)URL is a string (a list of character codes).
(url:url_term/1)BaseURLTerm specifies a URL.
The following properties should hold upon exit:
(url:url_term/1)URLTerm specifies a URL.

Documentation on imports

This module has the following direct dependencies:

System library modules:
lists, http_grammar.
Packages:
prelude, initial, condcomp, assertions, assertions/assertions_basic, isomodes, regtypes, dcg, doccomments.