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// Namespace Merging Example
// This demonstrates how TypeScript merges namespaces with the same name

// In TypeScript, we'd define namespaces like:
// namespace Validation {
//   export interface StringValidator {
//     isValid(s: string): boolean;
//   }
// }
//
// namespace Validation {
//   export interface NumberValidator {
//     isValid(n: number): boolean;
//   }
//   
//   export class ZipCodeValidator implements StringValidator {
//     isValid(s: string): boolean {
//       return s.length === 5 && /^\d+$/.test(s);
//     }
//   }
// }

// In JavaScript, namespaces compile to objects/modules

// Create equivalent namespace structure in JavaScript
var Validation = Validation || {};

// First namespace part (simulated)
(function(Validation) {
  // StringValidator would be an interface in TypeScript
  // No runtime representation of interfaces
})(Validation);

// Second namespace part (simulated)
(function(Validation) {
  // ZipCodeValidator implementation
  Validation.ZipCodeValidator = function() {};
  
  Validation.ZipCodeValidator.prototype.isValid = function(s) {
    return s.length === 5 && /^\d+$/.test(s);
  };
})(Validation);

// Using the "merged" namespace
console.log("Using the ZipCodeValidator from merged namespace:");
var zipValidator = new Validation.ZipCodeValidator();

console.log('zipValidator.isValid("12345"): ' + zipValidator.isValid("12345")); // true
console.log('zipValidator.isValid("1234"): ' + zipValidator.isValid("1234"));   // false
console.log('zipValidator.isValid("abcde"): ' + zipValidator.isValid("abcde")); // false

console.log("\nIn TypeScript, the merged namespace would look like:");
console.log("namespace Validation {");
console.log("  export interface StringValidator { isValid(s: string): boolean; }");
console.log("  export interface NumberValidator { isValid(n: number): boolean; }");
console.log("  export class ZipCodeValidator implements StringValidator {");
console.log("    isValid(s: string): boolean {");
console.log("      return s.length === 5 && /^\\d+$/.test(s);");
console.log("    }");
console.log("  }");
console.log("}");

Using the ZipCodeValidator from merged namespace:
zipValidator.isValid("12345"): true
zipValidator.isValid("1234"): false
zipValidator.isValid("abcde"): false

In TypeScript, the merged namespace would look like:
namespace Validation {
  export interface StringValidator { isValid(s: string): boolean; }
  export interface NumberValidator { isValid(n: number): boolean; }
  export class ZipCodeValidator implements StringValidator {
    isValid(s: string): boolean {
      return s.length === 5 && /^\d+$/.test(s);
    }
  }
}