assignObjectsFromPairs — GTM Variable Template for Object

VARIABLES › OBJECT

assignObjectsFromPairs EXTENDED Object

Direct (.tpl) Apply (.tpl)

Merges key-value pair objects from a GTM table.

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Examples

Merge pair objects

INPUT

Base Object: {name: 'John', age: 30}
ext: [{key: 'city', val: 'Paris'}, {key: 'country', val: 'France'}]

OUTPUT

John

Override existing keys

INPUT

Base Object: {name: 'John', age: 30, city: 'London'}
ext: [{key: 'age', val: 35}, {key: 'city', val: 'Paris'}]

OUTPUT

John

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GTM Configuration

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Read-only Preview

assignObjectsFromPairs

Base Object

💾 The base object to merge into.

Supported formats:
  ✓ Object

Properties to assign

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

Supported formats:
  ✓ Object

*** Merge pair objects***

*** Override existing keys***

KeyValue

⊖

⊖

Add Row

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.

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Related Variables

Same category: Object

→ applyFromObject → assignDefaults → assignDefaultsDeep → assignObjects → entries → getKeys → getValue → getValueByPath → has → hasKeyEqualTo → hasNested → mergeConcat → mergeConcatDeep → omit → parseJsonString → pick → pickNested → set → toObjectPairs → values → zipObject

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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 makeTableMap = require('makeTableMap');

const assign = function(sourceObject, additionalObject) {
    // Copy all properties from additionalObject to sourceObject
    for (let key in additionalObject) {
        sourceObject[key] = additionalObject[key];
    }
    return sourceObject;
};

const toObjectPairs = function(simpleTable) {
    return makeTableMap(simpleTable, "key", "val");
};
const safeFunction = fn => typeof fn === 'function' ? fn : x => x;
const out = safeFunction(data.out);
// ===============================================================================
// assignObjectsFromPairs - Direct mode
// ===============================================================================
const applyCast = (castFn, value) => safeFunction(castFn)(value);
const value = applyCast(data.pre, data.src);
return out(assign(value, toObjectPairs(data.ext)));
// ===============================================================================
// assignObjectsFromPairs(...) – Apply Mode
// ===============================================================================
/*
return function(value, additionalObject) {
   additionalObject = data.rp1 ? data.ext : additionalObject;
   return out(assign(value, additionalObject));
};
*/

🧪 View Test Scenarios (5 tests)

✅ '[example] Merge pair objects'
✅ '[example] Override existing keys'
✅ Test with empty additional object
✅ Test with empty source object
✅ Test with mixed value types