chunk — GTM Variable Template for Array

VARIABLES › ARRAY

chunk EXTENDED Array

Direct (.tpl) Apply (.tpl)

Splits an array into groups of the specified size.

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Examples

Split into equal chunks▶ Try

INPUT

Array To Split: [1, 2, 3, 4, 5, 6]
Chunk Size: 2

OUTPUT

[[1, 2], [3, 4], [5, 6]]

Remainder in last chunk▶ Try

INPUT

Array To Split: [1, 2, 3, 4, 5, 6, 7]
Chunk Size: 3

OUTPUT

[[1, 2, 3], [4, 5, 6], [7]]

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GTM Configuration

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chunk

Read-Only Try Live

Array To Split

💾 The array to split into chunks.

Supported formats:
  ✓ Array

Chunk Size

🎯 The size of each chunk (must be >= 1).

Supported formats:
  ✓ Number
  ✓ String

Input Setup

Input Function (optional)

⚙️ Optional pre-processing function applied to the input before internal logic (e.g., convert object to string, normalize case). Internal transformations such as case handling will still apply afterward.

Result Handling

Output Function (optional)

⚙️ Optional function to apply to the result before returning it (e.g., str => str + ' €', val => val !== undefined for boolean conversion). Useful for chaining transformations on the output.

Array To Split array

💡 Type any text to see the result update live

🎯 Using special value — click input to type instead

Test with:

Falsy undefined null "" empty 0 false NaN

Truthy true 42 "hello" {} empty [] empty {a:1} [1,2,3]

Chunk Size number

🔗 Result Handling — Chain Variables

Chain apply-mode variables to the output. Each variable receives the result of the previous one.

chunk()

+ Chain another variable

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Related Variables

Same category: Array

→ compact → dropItems → dropItemsRight → every → filterArray → find → findIndexByCallback → findIndexByRegex → flatten → head → includesAll → includesAny → includesNone → indexOf → join → last → lastIndexOf → reduce → reduceRight → reverse → selectFromArray → some → sort → tail → takeItems → takeItemsRight → uniq → wrapInArray

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Under the Hood

📜 View Implementation Code

/**
* Splits an array into chunks of the specified size.
* 
* @param {Array} data.src - The array to split into chunks.
* @param {number|string} data.siz - The size of each chunk (must be >= 1).
* @param {Function|string} [data.out] - Optional output handler: function to transform result or string with format.
*
* Direct-mode specific parameters:
* @param {Function} [data.pre] - Optional pre-processor function to transform src before chunking.
* 
* @returns {Array[]} A new array containing sub-arrays (chunks) of the specified size. The last chunk may be smaller if the array can't be split evenly.
*
* @framework ggLowCodeGTMKit
*/
const getType = require('getType');
const makeNumber = require('makeNumber');

const chunk = function(arr, size) {
   const sizeNum = makeNumber(size);
   if (getType(arr) !== 'array' || typeof sizeNum !== 'number' || sizeNum < 1) {
       return [];
   }
   const result = [];
   for (let i = 0; i < arr.length; i += sizeNum) {
       result.push(arr.slice(i, i + sizeNum));
   }
   return result;
};
const safeFunction = fn => typeof fn === 'function' ? fn : x => x;
const out = safeFunction(data.out);
// ===============================================================================
// chunk - Direct mode
// ===============================================================================
const applyCast = (castFn, value) => safeFunction(castFn)(value);
const value = applyCast(data.pre, data.src);
return out(chunk(value, data.siz));
// ===============================================================================
// chunk(...) – Apply Mode
// ===============================================================================
/*
return function(value, size) {
   size = data.rp1 ? data.siz : size;
   return out(chunk(value, size));
};
*/

🧪 View Test Scenarios (5 tests)

✅ '[example] Split into equal chunks'
✅ '[example] Remainder in last chunk'
✅ String size parameter - converts to number and chunks
✅ Invalid size less than 1 - returns empty array
✅ Non-array input - returns empty array