<li>If <var>serializedData</var> is not null, and if required

by the specification that defines the

<var>paymentMethod</var>.<a>supportedMethods</a>:

<ol>

<li>Let <var>object</var> be the result of

<a data-cite="ECMASCRIPT#sec-json.parse">JSON-parsing</a>

<var>serializedData</var>.

</li>

<li>

<p>

<a data-lt="converting">Convert</a> <var>object</var>

to an IDL value of the type specified by the

specification that defines the

<var>paymentMethod</var>.<a>supportedMethods</a>

(e.g., a <a data-cite=

"payment-method-basic-card#dom-basiccardrequest">BasicCardRequest</a>

in the case of [[?payment-method-basic-card]]).

Rethrow any exceptions.

</p>

<p class="note">

This step assures that any IDL type conversion errors

are caught as early as possible.

</p>

</li>

</ol>

</li>