Namespaced Validators

namespace Validation {
  export interface StringValidator {
    isAcceptable(s: string): boolean;
  }
 
  const lettersRegexp = /^[A-Za-z]+$/;
  const numberRegexp = /^[0-9]+$/;
 
  export class LettersOnlyValidator implements StringValidator {
    isAcceptable(s: string) {
      return lettersRegexp.test(s);
    }
  }
 
  export class ZipCodeValidator implements StringValidator {
    isAcceptable(s: string) {
      return s.length === 5 && numberRegexp.test(s);
    }
  }
}
 
// Some samples to try
let strings = ["Hello", "98052", "101"];
 
// Validators to use
let validators: { [s: string]: Validation.StringValidator; } = {};
validators["ZIP code"] = new Validation.ZipCodeValidator();
validators["Letters only"] = new Validation.LettersOnlyValidator();
 
// Show whether each string passed each validator
for (let s of strings) {
  for (var name in validators) {
    console.log(`"${ s }" - ${ validators[name].isAcceptable(s) ? "matches" : "does not match" } ${ name }`);
  }
}

Links:

https://www.typescriptlang.org/docs/handbook/namespaces.html#namespaced-validators

doc_TypeScript

2025-01-10 15:47:30

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