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

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<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>

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swi-prolog-nox 6.6.6-5 / usr / lib / swi-prolog / doc / Manual / apply.html
