---
category: [Administration & Integrations, Platform and Product Extensions, Platform and Product Extensions/Integration, Administration & Integrations/Custom Integrations & Apps, Platform and Product Extensions/Workday Extend]
keyword: [Extend, PMD Scripting, Scripts]
nav: wcp_docs
parent_url: /wcp_docs/
title: map (closure(item, index))
layout: subsection
---

## <a id="section_m3p_myb_5db"></a>Description

Creates a new list containing the results of calling the specified function on every element in the list. The closure function accepts a 2nd parameter, which is a zero-based index for generating the list.

## <a id="section_cyq_j1m_zsb"></a>Return Type

`List`

## <a id="section_dz5_pwg_5db"></a>Instance Method Syntax

```
thisList.map(closure(item, index))
```

<table><thead><tr><th>Parameter</th><th>Description</th></tr></thead><tbody><tr><td>closure</td><td>The function that creates each element. The closure function accepts a 2nd parameter, a zero-based index for implementing incremental logic. <p>Within a closure, you can't redefine the variables that are declared outside the closure.</p></td></tr></tbody></table><br/>

<b>Example</b>

`[ "a", "b", "c" ].map((item, index) => item + index)`

Returns `[ "a0", "b1", "c2" ]`

In this next example, <i>logos</i> is a Graph API mutation input variable, which is a collection of `attachmentContent` fields. The `map` function takes the list of rows from a `fileUploader` widget, and returns a list of `attachmentContent` objects. The `attachmentContent` value specifies part name, which is <i>file</i> appended by a zero-based index.

```
"logos": "<%
 myFileUploader.rows.map((row, index) => {
 {
   'attachmentContent': 'file' + index,
 }
});
%>"
 
```

## <a id="section_njs_xzl_zsb"></a>Namespace Function Syntax

```
list:map(list, closure(item,index))
```

<table><thead><tr><th>Parameter</th><th>Description</th></tr></thead><tbody><tr><td>list</td><td>The input List.</td></tr><tr><td>closure</td><td>The function that creates each element. The closure function accepts a 2nd parameter, a zero-based index for implementing incremental logic.</td></tr></tbody></table><br/>