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{{Template:Arraylist:Print subtitle}}
{{Template:Arraylist:Print subtitle}}
[[Category:Arraylist methods|Print subroutine]]
The <var>Print</var> subroutine displays the contents of an <var>Arraylist</var> in a readable form to the user current standard output (terminal) device.  The listed item values are displayed in ascending order by their position and, by default, are preceded by their item number, a colon and a blank space (<code>': '</code>).
<!--DPL?? Category:<var>Arraylist</var> methods|<var>Print</var> subroutine: <var>Print</var> <var>Arraylist</var>-->
<p><var>Print</var> is identical to <var>[[Audit (Arraylist subroutine)|Audit]]</var> and <var>[[Trace (Arraylist subroutine)|Trace]]</var>, except their output is sent to the <var class="product">Model 204</var> audit trail (like the <var class="product">User Language</var> <var>Audit</var> statement) and trace destinations, respectively.</p>
<p>
<var>Print</var> is a member of the [[Arraylist class]].
</p>


This subroutine displays the contents of an <var>Arraylist</var> on the user's
standard output device, typically a terminal.
The list item values, displayed in ascending order by their position,
are preceded by their item number, which by default
is followed by a colon (<tt>:</tt>) and a blank.
==Syntax==
==Syntax==
{{Template:Arraylist:Print syntax}}
{{Template:Arraylist:Print syntax}}
===Syntax terms===
===Syntax terms===
<table class="syntaxTable">
{{Template:PrintAuditTrace Arraylist syntax terms}}
<tr><th>al</th>
<td>An <var>Arraylist</var> object. </td></tr>
<tr><th><i>method</i></th>
<td>The method that is applied to <var class="term">al</var> items to produce the printed output. The method must take no parameters and produce an intrinsic (<var>Float</var>, <var>String</var>, <var>Fixed</var>, <var>Unicode</var>) value. It may be a system or user-written method, a class variable or property, a local method, or a [[Method variables|method variable]].
The default value of <var class="term">method</var> is <var>ToString</var>.</td></tr>
<tr><th>numWidth</th>
<td>The number of bytes in the display of each item to use for the item number. This is an optional parameter; if you specify a value, the parameter name <var>NumWidth</var> is required.
Item numbers are right-justified within the indicated number of bytes, and they are truncated on the left if the length of the item number exceeds the space allocated for it. The width must be a number between -1 and 10 inclusive. If you specify a value of 0, the item number is not displayed.
 
If <var class="term">numWidth</var> is -1, the default, the method uses the minimum number of bytes required to show the item number. For example, one byte is required for item number 5, while five bytes are required for item number 98764. </td></tr>
<tr><th>separator</th>
<td>A string, 15 characters or less, to be used to separate the item number from the item value.
This is an optional argument whose default is a colon (<code>:</code>). A blank always follows the <var class="term">separator</var> string. If you specify a value, the parameter name <var>Separator</var> is required.</td></tr>
<tr><th>start</th>
<td>The item number of the initial item in the output display. This is an optional argument, and it defaults to 1. If you specify a value, the parameter name <var>Start</var> is required.</td></tr>
<tr><th>maxItems</th>
<td>The maximum number of items to display. A zero or negative value means to display all the items.
This is an optional argument, and it defaults to zero. If you specify a value, the parameter name <var>MaxItems</var> is required.</td></tr>
<tr><th>label</th>
<td>A literal string that gets output before each line. This is useful for "tagging" lines to make them more identifiable.
This is an optional argument whose default is a null string. If you specify a value, the parameter name <var>Label</var> is required.</td></tr>
</table>


==Usage notes==
==Usage notes==
<ul>
<ul>
<li>All errors in <var>Print</var> result in request cancellation.
<li>All errors in <var>Print</var> result in request cancellation.
<li><var>[[Audit (Arraylist subroutine)|Audit]]</var> and <var>[[Trace (Arraylist subroutine)|Trace]]</var> are
the same as <var>Print</var> except they send their output to the audit trail
and selected trace destination, respectively.
<li>For examples of <var>Print</var> method calls, see [[Collections#Printing a collection|Printing a collection]].
</ul>
</ul>
==Examples==
For examples of the <var>Print</var> method calls, see [[Collections#Printing a collection|"Printing a collection"]].
==See also==
{{Template:Arraylist:Print footer}}

Latest revision as of 20:45, 8 August 2012

Print Arraylist (Arraylist class)

The Print subroutine displays the contents of an Arraylist in a readable form to the user current standard output (terminal) device. The listed item values are displayed in ascending order by their position and, by default, are preceded by their item number, a colon and a blank space (': ').

Print is identical to Audit and Trace, except their output is sent to the Model 204 audit trail (like the User Language Audit statement) and trace destinations, respectively.

Syntax

al:Print[( [itemFunction], [NumWidth= number], [Separator= string], - [Start= number], [MaxItems= number], [Label= string])]

Syntax terms

al An Arraylist object.
itemFunction The method that is to be applied to al items to produce the trace output. The method must take no parameters and produce an intrinsic (Float, String, Fixed or Unicode) value. It may be a system or user-written method, a class variable or property, a local method, or a method variable.

The default value of itemFunction is ToString.

NumWidth The number of bytes in the display of each item to use for the item number. This is an optional, name required, parameter; if you specify a value, the parameter name, NumWidth, is required.

Item numbers are right-justified within the indicated number of bytes, and they are truncated on the left if the length of the item number exceeds the space allocated for it. The NumWidth value must be a number between -1 and 10 inclusive. If you specify a value of 0, the item number is not displayed.

If NumWidth is -1, the default, the method uses the minimum number of bytes required to show the item number. For example, one byte is required for item number 5, while five bytes are required for item number 98764.

Separator A string, 15 characters or fewer, to be used to separate the item number from the item value. This is an optional, name required, argument; if you specify a value, the parameter name, Separator, is required.

The default value for Separator is a colon (:). A blank always follows the Separator string.

Start The item number of the initial item in the output display. This is an optional, name required, argument; if you specify a value, the parameter name, Start, is required.

The default value for Start is 1, which begins the output display with the first item in al.

MaxItems The maximum number of items to display. A zero or negative value means to display all the items. This is an optional, name required, argument; if you specify a value, the parameter name, MaxItems, is required.

The default value for MaxItems is 0, which displays all items from the Start item to the end of al.

Label A literal string that gets output before each line. This is useful for "tagging" lines to make them more identifiable. This is an optional, name required, argument; if you specify a value, the parameter name, Label, is required.

The default value for Label is a null string, which displays no additional "tag" information.

Usage notes

  • All errors in Print result in request cancellation.

Examples

For examples of the Print method calls, see "Printing a collection".

See also