uniq — GTM Variable Template for Array

VARIABLES › ARRAY

uniq EXTENDED Array

Direct (.tpl) Apply (.tpl) Add to GTM

Returns a new array with only unique values, removing all duplicates.

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When to Use This

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Examples

Remove duplicates▶ Try

INPUT

Array: [1, 2, 2, 3, 4, 3, 5]

OUTPUT

[1, 2, 3, 4, 5]

No duplicates unchanged▶ Try

INPUT

Array: [1, 2, 3, 4, 5]

OUTPUT

[1, 2, 3, 4, 5]

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Live Sandbox

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uniq

Read-Only Try Live

Array

💾 The array to process for unique values.

Supported formats:
  ✓ Array

Input Setup

Input Function (optional)

⚙️ Optional pre-processing function applied to the input before internal logic (e.g., convert string to array, filter values). Internal transformations will still apply afterward.

Result Handling

Output Function (optional)

⚙️ Optional function to apply to the result before returning it (e.g., arr => arr.length, arr => arr.join(',')). Useful for chaining transformations on the output.

Array 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]

🔗 Result Handling — Chain Variables

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

uniq()

+ Chain another variable

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Related Variables

Same category: Array

→ chunk → compact → dropItems → dropItemsRight → every → filterArray → find → findIndexByCallback → findIndexByRegex → flatten → head → includesAll → includesAny → includesNone → join → last → lastIndexOf → map → reduce → reduceRight → reverse → selectFromArray → some → sort → tail → takeItems → takeItemsRight → wrapInArray → ⚡ ARRAY › From Indexed Values → ⚡ ARRAY › From Values

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Under the Hood

📜 View Implementation Code

/**
 * Returns a new array with only unique values, removing all duplicates.
 *
 * @param {Array} data.src - The array to process for unique values.
 * @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 getting unique values.
 *
 * @returns {Array} A new array containing only unique values from the input array.
 *
 * @framework ggLowCodeGTMKit
 */
const getType = require('getType');

const uniq = function(value) {
   if (getType(value) !== 'array') { return []; }
   const result = [];
   for (let i = 0; i < value.length; i++) {
      const val = value[i];
      let found = false;
      for (let j = 0; j < result.length; j++) {
         if (result[j] === val || (val !== val && result[j] !== result[j])) { // Handle NaN
            found = true;
            break;
         }
      }
      if (!found) {
         result.push(val);
      }
   }
   return result;
};

const safeFunction = fn => typeof fn === 'function' ? fn : x => x;
const out = safeFunction(data.out);

// ===============================================================================
// uniq - Direct mode
// ===============================================================================
const applyCast = (castFn, value) => safeFunction(castFn)(value);
const value = applyCast(data.pre, data.src);
return out(uniq(value));

// ===============================================================================
// uniq() – Apply Mode: runtime parameter
// ===============================================================================
/*
return function(value) {
   return out(uniq(value));
};
*/

🧪 View Test Scenarios (8 tests)

✅ '[example] Remove duplicates'
✅ Array with string duplicates - should return unique strings
✅ '[example] No duplicates unchanged'
✅ Empty array - should return empty array
✅ Non-array input - should return empty array
✅ Array with mixed types - should handle different types
✅ Single element array - should return same array
✅ Array with undefined and null - should handle special values