List (Stringlist function): Difference between revisions

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{{Template:Stringlist:List subtitle}}
{{Template:Stringlist:List subtitle}}


This shared function is a virtual constructor, or factory method, for <var>Stringlist</var>s. The <var>List</var> method invokes the creation of a new <var>Stringlist</var> instance, then populates that instance with items that are, respectively, the values of the method arguments.
This shared function is a virtual constructor, or factory method, for <var>sStringlists</var>. The <var>List</var> method invokes the creation of a new <var>stringlist</var> instance, then populates that instance with items that are, respectively, the values of the method arguments.


==Syntax==
==Syntax==
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===Syntax terms===
===Syntax terms===
<table class="syntaxTable">
<table class="syntaxTable">
<tr><th>%sl</th>
<tr><th>%newlist</th>
<td>A declared or existing <var>Stringlist</var> object.</td></tr>
<td>A declared or existing <var>stringlist</var> object.</td></tr>
<tr><th>itemlist</th>
<tr><th>itemlist</th>
<td>A comma-delimited set of strings, each of which, from left to right, becomes an item in the resultant new <var>Stringlist</var>, '''%sl'''.</td></tr>
<td>A comma-delimited set of strings, each of which, from left to right, becomes an item in the resultant new <var>stringlist</var>, <var class="term">%newlist</var>.</td></tr>
</table>
</table>


==Usage notes==
==Usage notes==
<ul>
<ul>
<li>The <var>List</var> method requires at least one argument, which may be null.
<li><var>list</var> requires at least one argument, which may be null.<li>If an existing <var>stringlist</var> is set to receive the result of <var>list</var>, then any existing item(s) in that <var>stringlist</var> are entirely removed before the new item(s) are added.<li>The maximum number of <var class="term">itemlist</var> values is 62.<li>See factory methods for more information.</ul>
<li>If an existing <var>Stringlist</var> is set to receive the result of the <var>List</var> method, the items in that <var>Stringlist</var> are entirely removed; then the new items are added.<li>The maximum number of '''itemlist''' values is 62.<li><var>List</var> is a constructor and as such can be called with no method object, with an explicit class name, or with an object variable, even if that object is null:
<p class="output">%sl = <var>List</var>(<i>itemlist</i></i>
%sl = %(<var>Stringlist</var>):<var>List</var>(<i>itemlist</i></i>
%sl = %sl2:<var>List</var>(<i>itemlist</i></i>
</p>
<li>See factory methods for more information.
</ul>


==Examples==
==Examples==
<ul>
<ul><li><var>List</var> is a constructor and as such can be called with no method object, with an explicit class name, or with an object variable, even if that object is null:
<li>The following <var>List</var> method call creates a new <var>Stringlist</var> instance whose three items are, respectively, the strings <tt>.Moe</tt>, <tt>.Larry</tt>, and <tt>.Curly</tt>:
<p class="output">%sl = List(<i>itemlist</i>)
%sl = %(Stringlist):List(<i>itemlist</i>)
%sl = %sl2:List(<i>itemlist</i>)
</p>
<li>The following <var>list</var> method call creates a new <var>stringlist</var> instance whose three items are, respectively, the strings <var class="term">Moe</var>, <var class="term">Larry</var>, and <var class="term">Curly</var>:
<p class="code">%sl is object stringlist
<p class="code">%sl is object stringlist
%sl = list('Moe', 'Larry', 'Curly')
%sl = list('Moe', 'Larry', 'Curly')
</p>
</p>
<li>You can use the <var>List</var> method in contexts where a <var>Stringlist</var> is a method parameter. For example, the Run method of the <var>Daemon</var> class takes a <var>Stringlist</var> object as an argument. A <var>List</var> method call can be used for such an argument, as shown below:
<li>You can use the <var>list</var> method in contexts where a <var>stringlist</var> is a method parameter. For example, the <var>[[Run (Daemon function)|Run]]</var> method of the <var>daemon</var> class takes a <var>stringlist</var> object as an argument. A <var>list</var> method call can be used for such an argument, as shown below:
<p class="code">%d is object daemon
<p class="code">%d is object daemon
...
...
%d:run(%(stringlist):list('*LOWER', 'b', -
%d:run(%(stringlist):list('*LOWER', 'b', -
'printText Whatever', 'printText More', 'end')):print
                          'printText Whatever', 'printText More', 'end')):print
</p>
</p>


It is necessary above to specify the class <tt>.%(<var>Stringlist</var>):</tt> preceding the keyword <tt>.<var>List</var></tt>, because <var>String</var>s are also valid in the first argument for Run, and <tt>.<var>List</var></tt> without a qualifier could be interpreted as a field called <tt>.<var>List</var></tt>.
It is necessary above to specify the class <var class="term">%(Stringlist):</var> preceding the keyword <var>list</var>, because strings are also valid in the first argument for <var>[[Run (Daemon function)|Run]]</var>, and <var>list</var>; without a qualifier it could be interpreted as a field called <var class="term">list</var>.<li>
However, in a case where a <var>Stringlist</var> argument is expected, you can specify the <tt>.<var>List</var></tt> keyword without a qualifier. For example, a user method called Stuffit takes a <var>Stringlist</var> input:
However, cases where a <var>stringlist</var> argument is expected, you can specify the <var>List</var> keyword without a qualifier. For example, a user method called Stuffit takes a <var>stringlist</var> input:


<p class="code">%foo:stuffit(list('Hickory', 'Dickory', 'Doc'))
<p class="code">%foo:stuffit(list('Hickory', 'Dickory', 'Doc'))

Revision as of 07:25, 26 January 2011

Construct a new Stringlist from list of strings (Stringlist class)


This shared function is a virtual constructor, or factory method, for sStringlists. The List method invokes the creation of a new stringlist instance, then populates that instance with items that are, respectively, the values of the method arguments.

Syntax

%newList = [%(Stringlist):]List( itemList)

Syntax terms

%newlist A declared or existing stringlist object.
itemlist A comma-delimited set of strings, each of which, from left to right, becomes an item in the resultant new stringlist, %newlist.

Usage notes

  • list requires at least one argument, which may be null.
  • If an existing stringlist is set to receive the result of list, then any existing item(s) in that stringlist are entirely removed before the new item(s) are added.
  • The maximum number of itemlist values is 62.
  • See factory methods for more information.

Examples

  • List is a constructor and as such can be called with no method object, with an explicit class name, or with an object variable, even if that object is null:

    %sl = List(itemlist) %sl = %(Stringlist):List(itemlist) %sl = %sl2:List(itemlist)

  • The following list method call creates a new stringlist instance whose three items are, respectively, the strings Moe, Larry, and Curly:

    %sl is object stringlist %sl = list('Moe', 'Larry', 'Curly')

  • You can use the list method in contexts where a stringlist is a method parameter. For example, the Run method of the daemon class takes a stringlist object as an argument. A list method call can be used for such an argument, as shown below:

    %d is object daemon ... %d:run(%(stringlist):list('*LOWER', 'b', - 'printText Whatever', 'printText More', 'end')):print

    It is necessary above to specify the class %(Stringlist): preceding the keyword list, because strings are also valid in the first argument for Run, and list; without a qualifier it could be interpreted as a field called list.
  • However, cases where a stringlist argument is expected, you can specify the List keyword without a qualifier. For example, a user method called Stuffit takes a stringlist input:

    %foo:stuffit(list('Hickory', 'Dickory', 'Doc'))