N/render Module
render.EmailMergeResult
Object Description: Encapsulates an email merge result. Use render.mergeEmail(options) to create and return this object. For a complete list of this object’s properties, see EmailMergeResult Object Members.
Supported Script Types: Server-side scripts For more information, see SuiteScript 2.0 Script Types.
Module: N/render Module
Since: 2015.2
Search NetSuite - https://system.netsuite.com/app/help/helpcenter.nl?search=render.EmailMergeResult

// Code Example 1

//Add additional code

//...

var mergeResult = render.mergeEmail({

    templateId: 1234,

    entity: {

        type: 'employee',

        id: 62

        },

    recipient: {

        type: 'lead',

        id: 41

        },

    supportCaseId: 2,

    transactionId: 271,

    custmRecord: null

    });

//...

//Add additional code



//SOURCE: https://system.netsuite.com/app/help/helpcenter.nl?fid=section_4417244174.html