/usr/lib/swi-prolog/doc/Manual/apply.html

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">

<html>
<head>
<title>SWI-Prolog 7.1.10 Reference Manual: Section A.2</title><link rel="home" href="index.html">
<link rel="contents" href="Contents.html">
<link rel="index" href="DocIndex.html">
<link rel="summary" href="summary.html">
<link rel="previous" href="aggregate.html">
<link rel="next" href="assoc.html">

<style type="text/css">

/* Style sheet for SWI-Prolog latex2html
*/

dd.defbody
{ margin-bottom: 1em;
}

dt.pubdef, dt.multidef
{ color: #fff;
padding: 2px 10px 0px 10px;
margin-bottom: 5px;
font-size: 18px;
vertical-align: middle;
overflow: hidden;
}

dt.pubdef { background-color: #0c3d6e; }
dt.multidef { background-color: #ef9439; }

.bib dd
{ margin-bottom: 1em;
}

.bib dt
{ float: left;
margin-right: 1.3ex;
}

pre.code
{ margin-left: 1.5em;
margin-right: 1.5em;
border: 1px dotted;
padding-top: 5px;
padding-left: 5px;
padding-bottom: 5px;
background-color: #f8f8f8;
}

div.navigate
{ text-align: center;
background-color: #f0f0f0;
border: 1px dotted;
padding: 5px;
}

div.title
{ text-align: center;
padding-bottom: 1em;
font-size: 200%;
font-weight: bold;
}

div.author
{ text-align: center;
font-style: italic;
}

div.abstract
{ margin-top: 2em;
background-color: #f0f0f0;
border: 1px dotted;
padding: 5px;
margin-left: 10%; margin-right:10%;
}

div.abstract-title
{ text-align: center;
padding: 5px;
font-size: 120%;
font-weight: bold;
}

div.toc-h1
{ font-size: 200%;
font-weight: bold;
}

div.toc-h2
{ font-size: 120%;
font-weight: bold;
margin-left: 2em;
}

div.toc-h3
{ font-size: 100%;
font-weight: bold;
margin-left: 4em;
}

div.toc-h4
{ font-size: 100%;
margin-left: 6em;
}

span.sec-nr
{
}

span.sec-title
{
}

span.pred-ext
{ font-weight: bold;
}

span.pred-tag
{ float: right;
padding-top: 0.2em;
font-size: 80%;
font-style: italic;
color: #fff;
}

div.caption
{ width: 80%;
margin: auto;
text-align:center;
}

/* Footnotes */
.fn {
color: red;
font-size: 70%;
}

.fn-text, .fnp {
position: absolute;
top: auto;
left: 10%;
border: 1px solid #000;
box-shadow: 5px 5px 5px #888;
display: none;
background: #fff;
color: #000;
margin-top: 25px;
padding: 8px 12px;
font-size: larger;
}

sup:hover span.fn-text
{ display: block;
}

/* Lists */

dl.latex
{ margin-top: 1ex;
margin-bottom: 0.5ex;
}

dl.latex dl.latex dd.defbody
{ margin-bottom: 0.5ex;
}

/* PlDoc Tags */

dl.tags
{ font-size: 90%;
margin-left: 5ex;
margin-top: 1ex;
margin-bottom: 0.5ex;
}

dl.tags dt
{ margin-left: 0pt;
font-weight: bold;
}

dl.tags dd
{ margin-left: 3ex;
}

td.param
{ font-style: italic;
font-weight: bold;
}

/* Index */

dt.index-sep
{ font-weight: bold;
font-size: +1;
margin-top: 1ex;
}

/* Tables */

table.center
{ margin: auto;
}

table.latex
{ border-collapse:collapse;
}

table.latex tr
{ vertical-align: text-top;
}

table.latex td,th
{ padding: 2px 1em;
}

table.latex tr.hline td,th
{ border-top: 1px solid black;
}

table.frame-box
{ border: 2px solid black;
}

</style>
</head>
<body style="background:white">
<div class="navigate"><a class="nav" href="index.html"><img src="home.gif" alt="Home"></a>
<a class="nav" href="Contents.html"><img src="index.gif" alt="Contents"></a>
<a class="nav" href="DocIndex.html"><img src="yellow_pages.gif" alt="Index"></a>
<a class="nav" href="summary.html"><img src="info.gif" alt="Summary"></a>
<a class="nav" href="aggregate.html"><img src="prev.gif" alt="Previous"></a>
<a class="nav" href="assoc.html"><img src="next.gif" alt="Next"></a>
</div>
<h2 id="sec:apply"><a id="sec:A.2"><span class="sec-nr">A.2</span> <span class="sec-title">library(apply): 
Apply predicates on a list</span></a></h2>

<p><a id="sec:apply"></a>

<dl class="tags">
<dt class="mtag">See also</dt>
<dd>
- <code>apply_macros.pl</code> provides compile-time expansion for part 
of this library. <br>
- <a class="url" href="http://www.cs.otago.ac.nz/staffpriv/ok/pllib.htm">http://www.cs.otago.ac.nz/staffpriv/ok/pllib.htm</a>
</dd>
<dt class="tag">To be done</dt>
<dd>
Add <span class="pred-ext">include/4</span>, <span class="pred-ext">include/5</span>, <span class="pred-ext">exclude/4</span>, <span class="pred-ext">exclude/5</span>
</dd>
</dl>

<p>This module defines meta-predicates that apply a predicate on all 
members of a list.

<dl class="latex">
<dt class="pubdef"><span class="pred-tag">[det]</span><a id="include/3"><strong>include</strong>(<var>:Goal, 
+List1, ?List2</var>)</a></dt>
<dd class="defbody">
Filter elements for which <var>Goal</var> succeeds. True if <var>List2</var> 
contains those elements Xi of <var>List1</var> for which <code>call(Goal, Xi)</code> 
succeeds.

<dl class="tags">
<dt class="tag">See also</dt>
<dd>
Older versions of SWI-Prolog had <span class="pred-ext">sublist/3</span> 
with the same arguments and semantics.
</dd>
</dl>

</dd>
<dt class="pubdef"><span class="pred-tag">[det]</span><a id="exclude/3"><strong>exclude</strong>(<var>:Goal, 
+List1, ?List2</var>)</a></dt>
<dd class="defbody">
Filter elements for which <var>Goal</var> fails. True if <var>List2</var> 
contains those elements Xi of <var>List1</var> for which <code>call(Goal, Xi)</code> 
fails.</dd>
<dt class="pubdef"><span class="pred-tag">[det]</span><a id="partition/4"><strong>partition</strong>(<var>:Pred, 
+List, ?Included, ?Excluded</var>)</a></dt>
<dd class="defbody">
Filter elements of <var>List</var> according to <var>Pred</var>. True if <var>Included</var> 
contains all elements for which <code>call(Pred, X)</code> succeeds and
<var>Excluded</var> contains the remaining elements.</dd>
<dt class="pubdef"><span class="pred-tag">[semidet]</span><a id="partition/5"><strong>partition</strong>(<var>:Pred, 
+List, ?Less, ?Equal, ?Greater</var>)</a></dt>
<dd class="defbody">
Filter <var>List</var> according to <var>Pred</var> in three sets. For 
each element Xi of <var>List</var>, its destination is determined by <code>call(Pred, Xi, Place)</code>, 
where Place must be unified to one of <code>&lt;</code>, <code>=</code> 
or <code>&gt;</code>.
<var>Pred</var> must be deterministic.</dd>
<dt class="pubdef"><a id="maplist/2"><strong>maplist</strong>(<var>:Goal, 
?List</var>)</a></dt>
<dd class="defbody">
True if <var>Goal</var> can successfully be applied on all elements of
<var>List</var>. Arguments are reordered to gain performance as well as 
to make the predicate deterministic under normal circumstances.</dd>
<dt class="pubdef"><a id="maplist/3"><strong>maplist</strong>(<var>:Goal, 
?List1, ?List2</var>)</a></dt>
<dd class="defbody">
As <a class="pred" href="apply.html#maplist/2">maplist/2</a>, operating 
on pairs of elements from two lists.</dd>
<dt class="pubdef"><a id="maplist/4"><strong>maplist</strong>(<var>:Goal, 
?List1, ?List2, ?List3</var>)</a></dt>
<dd class="defbody">
As <a class="pred" href="apply.html#maplist/2">maplist/2</a>, operating 
on triples of elements from three lists.</dd>
<dt class="pubdef"><a id="maplist/5"><strong>maplist</strong>(<var>:Goal, 
?List1, ?List2, ?List3, ?List4</var>)</a></dt>
<dd class="defbody">
As <a class="pred" href="apply.html#maplist/2">maplist/2</a>, operating 
on quadruples of elements from four lists.</dd>
<dt class="pubdef"><a id="foldl/4"><strong>foldl</strong>(<var>:Goal, 
+List, +V0, -V</var>)</a></dt>
<dt class="pubdef"><a id="foldl/5"><strong>foldl</strong>(<var>:Goal, 
+List1, +List2, +V0, -V</var>)</a></dt>
<dt class="pubdef"><a id="foldl/6"><strong>foldl</strong>(<var>:Goal, 
+List1, +List2, +List3, +V0, -V</var>)</a></dt>
<dt class="pubdef"><a id="foldl/7"><strong>foldl</strong>(<var>:Goal, 
+List1, +List2, +List3, +List4, +V0, -V</var>)</a></dt>
<dd class="defbody">
Fold a list, using arguments of the list as left argument. The foldl 
family of predicates is defined by:

<pre class="code">
foldl(P, [X11,...,X1n], ..., [Xm1,...,Xmn], V0, Vn) :-
      P(X11, ..., Xm1, V0, V1),
      ...
      P(X1n, ..., Xmn, V', Vn).
</pre>

</dd>
<dt class="pubdef"><a id="scanl/4"><strong>scanl</strong>(<var>:Goal, 
+List, +V0, -Values</var>)</a></dt>
<dt class="pubdef"><a id="scanl/5"><strong>scanl</strong>(<var>:Goal, 
+List1, +List2, +V0, -Values</var>)</a></dt>
<dt class="pubdef"><a id="scanl/6"><strong>scanl</strong>(<var>:Goal, 
+List1, +List2, +List3, +V0, -Values</var>)</a></dt>
<dt class="pubdef"><a id="scanl/7"><strong>scanl</strong>(<var>:Goal, 
+List1, +List2, +List3, +List4, +V0, -Values</var>)</a></dt>
<dd class="defbody">
Left scan of list. The scanl family of higher order list operations is 
defined by:

<pre class="code">
scanl(P, [X11,...,X1n], ..., [Xm1,...,Xmn], V0,
      [V0,V1,...,Vn]) :-
      P(X11, ..., Xmn, V0, V1),
      ...
      P(X1n, ..., Xmn, V', Vn).
</pre>

<p></dd>
</dl>

<p></body></html>
swi-prolog-nox 6.6.4-2ubuntu1 / usr / lib / swi-prolog / doc / Manual / apply.html
