> ## Documentation Index
> Fetch the complete documentation index at: https://docs.alumio.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Array: Join into string

> Joins array items into a single string using a separator.

export const FormField = ({property, label, required = false, diType, uiPatterns, children}) => {
  const patterns = Array.isArray(uiPatterns) ? uiPatterns : uiPatterns ? [uiPatterns] : [];
  return <div style={{
    margin: '1.5rem 0'
  }}>
      <div style={{
    display: 'flex',
    alignItems: 'baseline',
    flexWrap: 'wrap',
    gap: '0.5rem',
    marginBottom: '0.25rem'
  }}>
        <strong>{label}</strong>
        <span style={{
    fontSize: '0.7rem',
    fontWeight: 600,
    textTransform: 'uppercase',
    letterSpacing: '0.04em',
    color: required ? '#6241f5' : '#6b7280'
  }}>
          {required ? 'Required' : 'Optional'}
        </span>
      </div>

      <div>{children}</div>

      {diType || patterns.length > 0 ? <p style={{
    fontSize: '0.85rem',
    color: '#6b7280',
    marginBottom: 0
  }}>
          {diType ? <>
              See the <a href={`/references/${diType}`}>{diType}</a> reference.{' '}
            </> : null}
          {patterns.length > 0 ? <>
              Accepts a <a href={`/documentation/placeholders-and-patterns/patterns#${patterns[0]}`}>pattern</a>.
            </> : null}
        </p> : null}
    </div>;
};

Use this mapper to glue all the items in a list together into one piece of text, with a separator of your choice placed between each item. It is the opposite of splitting text apart: handy for turning a list of tags into a comma-separated label, or a set of name parts into a single full name.

This documentation describes: [Schema](/schemas/mapper/list-concat)

## Fields

<FormField property="glue" label="Glue">
  The text placed between each item when they are joined. Common choices are a comma, a space, or a dash. Leave it empty to join the items with a single space.
</FormField>

## Sample data

This example joins a list of tags into one comma-separated label.

| Field | Value |
| ----- | ----- |
| Glue  | `, `  |

Input:

```json theme={null}
["summer", "sale", "outdoor"]
```

Output:

```json theme={null}
"summer, sale, outdoor"
```

```json Configuration theme={null}
{
  "prototype": "list-concat",
  "parameters": {
    "glue": ", "
  }
}
```