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toCamelCase — GTM Variable Template for String

VARIABLES › STRING
toCamelCase CORE String

Converts a string to camelCase format. Returns undefined if the input is not a valid string.


When to Use This

String Manipulation

Transform, clean, and normalize text data for consistent downstream processing.

Type Conversion

Safely convert between data types — strings, numbers, booleans, arrays, objects.

Formatting

Normalize casing, spacing, encoding, and presentation of data values.


Examples

Hyphens to camelCase
INPUT
String To Convert: hello-world-test
OUTPUT
helloWorldTest
Underscores to camelCase
INPUT
String To Convert: hello_world_test
OUTPUT
helloWorldTest
Non-string input returns undefined
INPUT
String To Convert: 12345
OUTPUT
undefined

GTM Configuration

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toCamelCase
String To Convert
💾 The string to convert to camel case format.

Supported formats:
  ✓ String
Input Setup
Input Function (optional)
⚙️ Optional pre-processing function applied to the input before internal logic (e.g., normalize case, clean string). Internal transformations such as camel case conversion will still apply afterward.
Result Handling
Output Function (optional)
⚙️ Optional function to apply to the result before returning it (e.g., str => str + 'Suffix', val => val.charAt(0).toUpperCase() + val.slice(1) for Pascal case). Useful for chaining transformations on the output.
String To Convert string
💡 Type any text to see the result update live
🎯 Using special value — click input to type instead
Test with:
Falsy
Truthy
toCamelCase()


Under the Hood

📜 View Implementation Code
/**
* Converts a string to camel case format.
* 
* @param {any} data.src - The string to convert to camel case.
* @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 conversion.
* 
* @returns {string|undefined} The string in camel case format, or undefined if the input is not a valid string.
*
* @framework ggLowCodeGTMKit
*/
const toCamelCase = function(string) {
   if (typeof string === 'string') {
       const pattern = "[_-]+";
       const replacement = ' ';
       
       const replaceAllWithRegex = function(input, pattern, replacement) {
           if (typeof input !== 'string' || typeof pattern !== 'string' || typeof replacement !== 'string') {
               return input;
           } 
           let result = input;
           let lastIndex = 0;
           
           while (lastIndex < result.length) {
               const remainingStr = result.substring(lastIndex);
               const matchObj = remainingStr.match(pattern);
               if (matchObj === null) {
                   break;
               }
           
               const actualMatchIndex = lastIndex + (matchObj.index || 0);
               
               result = result.substring(0, actualMatchIndex) + 
                        replacement + 
                        result.substring(actualMatchIndex + matchObj[0].length);
               lastIndex = actualMatchIndex + replacement.length;
           }
           return result;
       }; 
    
       
       let result = replaceAllWithRegex(string, pattern, replacement);
       
       result = result
           .split(' ')  
           .map((word, index) => {
               if (index === 0) {
                   return word.toLowerCase();
               }
               return word.charAt(0).toUpperCase() + word.slice(1).toLowerCase();
           })
           .join('');
       return result;
   }
   return undefined;
};
const safeFunction = fn => typeof fn === 'function' ? fn : x => x;
const out = safeFunction(data.out);
// ===============================================================================
// toCamelCase - Direct mode
// ===============================================================================
const applyCast = (castFn, value) => safeFunction(castFn)(value);
const value = applyCast(data.pre, data.src);
return out(toCamelCase(value));

// ===============================================================================
// toCamelCase() – Apply Mode
// ===============================================================================
/*
return function(value) {
  return out(toCamelCase(value));
};
*/
🧪 View Test Scenarios (5 tests)
✅ String with spaces - should convert to camelCase
✅ '[example] Hyphens to camelCase'
✅ '[example] Underscores to camelCase'
✅ Mixed case string with multiple separators - should convert to camelCase
✅ '[example] Non-string input returns undefined'