identity — GTM Variable Template for Value

VARIABLES › VALUE

identity EXTENDED Value

Direct (.tpl) Apply (.tpl)

Returns the input value unchanged. Useful as a passthrough function.

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Examples

String passthrough▶ Try

INPUT

Source Value: hello world

OUTPUT

hello world

Number passthrough▶ Try

INPUT

Source Value: 42

OUTPUT

42

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GTM Configuration

This is what you'll see when you open this variable in Google Tag Manager. Hover the icons for details.

identity

Read-Only Try Live

Source Value

💾 The input value to return as-is.

Supported formats:
  ✓ Any

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.

Source Value any

💡 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.

identity()

+ Chain another variable

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Related Variables

Same category: Value

→ NaN → apply → applyChain → emptyArray → emptyObject → emptyObjectArray → emptyString → false → falseTo → falsyTo → filterValue → getLength → getType → mapTruthiness → not → null → nullTo → parseValue → regexTableLookupAll → regexTableLookupCallback → true → undefinedTo → zero

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Under the Hood

📜 View Implementation Code

/**
* Returns the source value as-is.
* 
* @param {*} data.src - The input value to return.
* @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 returning.
* 
* @returns {*} Returns the input src, optionally transformed by out.
*
* @framework ggLowCodeGTMKit
*/
const identity = function(value) {
   return value;
};

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

// ===============================================================================
// identity - Direct mode
// ===============================================================================
const applyCast = (castFn, value) => safeFunction(castFn)(value);
const value = applyCast(data.pre, data.src);
return out(identity(value));
// ===============================================================================
// identity() – Apply Mode
// ===============================================================================
/*
return function(value) {
  return out(identity(value));
};
*/

🧪 View Test Scenarios (5 tests)

✅ '[example] String passthrough'
✅ '[example] Number passthrough'
✅ Object input - should return unchanged
✅ Boolean input - should return unchanged
✅ Null input - should return null