---
title: "concat · RUAL Documentation"
description: "Returns a joined array of two or more arrays."
canonical: https://docs.rual.nl/block-types/array/array_concat
language: en
---

# concat

This block is part of the [`array`](https://docs.rual.nl/block-types/array) group and was last modified in core [`v10.4.28`](https://docs.rual.nl/core-versions/100428).

Returns a joined array of two or more arrays.

- array_1 required `array` The first array to be concatenated.

- array_2 required `array` The second array to be concatenated.

- Array `array` The resulting array after concatenation.

Concatenates every connected input pin in pin order into one array: array inputs contribute their elements, and a non-array input is appended as a SINGLE element rather than skipped. Nil inputs are skipped; with no usable inputs the output is an empty array, never null.

| `multiple` |
| --- |

A typical wiring for [concat](https://docs.rual.nl/block-types/array/array_concat): [select field values](https://docs.rual.nl/block-types/array/array_get_values_from_bp_field) feeds the `array_1` pin; [add to top of array](https://docs.rual.nl/block-types/array/array_unshift) feeds the `array_2` pin; the `array` out pin feeds [remove duplicates](https://docs.rual.nl/block-types/array/array_remove_duplicates).

![Studio canvas example for the concat block: typical wiring for concat.](https://docs.rual.nl/canvas-examples/array_concat.png)

### Commonly used with

In production blueprints, this block is most often wired together with:

- [remove duplicates](https://docs.rual.nl/block-types/array/array_remove_duplicates): wired in both directions with this block. Removes duplicate values from an array.

- [select field values](https://docs.rual.nl/block-types/array/array_get_values_from_bp_field): wired in both directions with this block. returns an array with values of the given field in this array of objects.

- [add to top of array](https://docs.rual.nl/block-types/array/array_unshift): feeds into this block. Adds your given value to your given array.

- [search](https://docs.rual.nl/block-types/storage/function_search): feeds into this block. searches in the given storage based on a query.

- [select fields](https://docs.rual.nl/block-types/array/array_get_by_fields): feeds into this block. Filters all other fields from the objects in this array.

- [length](https://docs.rual.nl/block-types/array/array_length): this block feeds into it. Returns the total length of the given array.

### Version history

Introduced in [`v10.4.28`](https://docs.rual.nl/core-versions/100428).