JsonCircularReference class: Difference between revisions

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<table class="syntaxTable">
<table class="syntaxTable">


<tr><th>%JsonCircularReference </th>
<tr class="head"><th>%JsonCircularReference </th>
<td>A reference to an instance of a <var>JsonCircularReference</var> object.
<td>A reference to an instance of a <var>JsonCircularReference</var> object.
</td></tr>
</td></tr>


<tr><th><var>[%(JsonCircularReference):]</var></th><td>The class name in parentheses denotes a <var>[[Notation conventions for methods#Constructors|Constructor]]</var>. See [[#Usage notes|Usage notes]], below, for more information about invoking a <var>JsonCircularReference</var> <var>Constructor</var>.</td></tr>
<tr class="head"><th><var>[%(JsonCircularReference):]</var></th><td>The class name in parentheses denotes a <var>[[Notation conventions for methods#Constructors|Constructor]]</var>. See [[#Usage notes|Usage notes]], below, for more information about invoking a <var>JsonCircularReference</var> <var>Constructor</var>.</td></tr>
</table>
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Revision as of 20:08, 1 May 2015

JsonCircularReference exceptions are thrown by the Stringify function in the Json class if the Json object leads to a circular reference.

To produce a JsonCircularReference exception for yourself, you typically use a SOUL Throw statement with a JsonCircularReference New constructor. This statement must be issued from within a method, and it can only be caught by the code that calls the method. For example, the following statement throws a JsonCircularReference exception:

throw %(JsonCircularReference):new

Remember that you catch an exception with the Catch statement; if an exception condition occurs outside a Catch for it, the request is canceled.

The JsonCircularReference class, like the Json class is available as of Model 204 7.6.

The JsonCircularReference methods

The following are the available JsonCircularReference class methods.

MethodDescription
NewCreate a new JsonCircularReference object

The methods in the class are described in the subsections that follow. In addition:


New constructor

Create a new JsonCircularReference object (JsonCircularReference class)

This Constructor generates an instance of a JsonCircularReference exception. The New method format is as follows:

Syntax

%jsonCircularReference = [%(JsonCircularReference):]New

Syntax terms

%JsonCircularReference A reference to an instance of a JsonCircularReference object.
[%(JsonCircularReference):]The class name in parentheses denotes a Constructor. See Usage notes, below, for more information about invoking a JsonCircularReference Constructor.

Usage notes

The following example catches a circular reference exception and prints the string where the circular reference occurs.

b %jsonCircRefError is object JsonCircularReference %jsa is object json %jsb is object json %jsc is object json %jsa = array('a') %jsb = array('b') %jsc = array('c') %jsa:add(%jsb) %jsb:add(%jsc) %jsc:add(%jsa) try print %jsa:stringify catch JsonCircularReference to %jsonCircRefError print 'Caught Json Circular Reference Error' print %jsa:tostring end try end

Running this example results in:

Caught Json Circular Reference Error ["a",["b",["c",[Circular]]]]