assignObjects — GTM Variable Template for Object

VARIABLES › OBJECT

assignObjects EXTENDED Object

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

Merges two objects. Later properties override earlier ones.

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When to Use This

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Examples

Merge two objects▶ Try

INPUT

Base Object: {name: "John", age: 30}
Extension Object: {city: "Paris", country: "France"}

OUTPUT

{name: "John", age: 30, city: "Paris", country: "France"}

Override on conflict▶ Try

INPUT

Base Object: {name: "John", age: 30, city: "London"}
Extension Object: {city: "Paris", country: "France"}

OUTPUT

{name: "John", age: 30, city: "Paris", country: "France"}

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Live Sandbox

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assignObjects

Read-Only Try Live

Base Object

💾 The base object to merge into.

Extension Object

💾 An object whose properties will override or extend the base object.

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.

Base Object object

💡 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]

Extension Object object

🔗 Result Handling — Chain Variables

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

assign()

+ Chain another variable

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Related Variables

Same category: Object

→ applyFromObject → assignDefaults → assignDefaultsDeep → assignObjectsFromPairs → entries → getKeys → getValue → getValueByPath → has → hasKeyEqualTo → hasNested → mergeConcat → mergeConcatDeep → omit → pick → pickNested → set → toObjectPairs → values → zipObject → ⚡ OBJECT › From Arrays → ⚡ OBJECT › Smart → ⚡ OBJECT › Transformer (Advanced)

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Under the Hood

📜 View Implementation Code

/**
* Assigns properties from two objects into a new object.
*
* @param {Object} data.src - The base object.
* @param {Object} data.ext - An object whose properties will override or extend the base object.
* @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 merging.
*
* @returns {Object} A new object containing properties from both inputs.
*
* @framework ggLowCodeGTMKit
*/
const getType = require('getType');

const assign = function(sourceObject, additionalObject) {
   const result = {};
   if (getType(sourceObject) === 'object') {
       for (let key in sourceObject) {
           result[key] = sourceObject[key];
       }
   }
   if (getType(additionalObject) === 'object') {
       for (let key in additionalObject) {
           result[key] = additionalObject[key];
       }
   }
   return result;
};
const safeFunction = fn => typeof fn === 'function' ? fn : x => x;
const out = safeFunction(data.out);
// ===============================================================================
// assignObjects - Direct mode
// ===============================================================================
const applyCast = (castFn, value) => safeFunction(castFn)(value);
const value = applyCast(data.pre, data.src);
return out(assign(value, data.ext));
// ===============================================================================
// assignObjects(...) – Apply Mode
// ===============================================================================
/*
return function(value, additionalObject) {
   additionalObject = data.rp1 ? additionalObject : data.ext;
   return out(assign(value, additionalObject));
};
*/

🧪 View Test Scenarios (8 tests)

✅ '[example] Merge two objects'
✅ '[example] Override on conflict'
✅ Empty source object - returns only extension properties
✅ Empty extension object - returns only source properties
✅ Both empty objects - returns empty object
✅ Non-object source - handles invalid source
✅ Non-object extension - handles invalid extension
✅ Both non-objects - handles both invalid