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Function: tryCatch()

Call Signature​

tryCatch<T>(fn): Validation<T, unknown>

Defined in: validation/constructors/index.ts:197

Wraps a potentially throwing function in a Validation.

If the function succeeds, returns Valid with the return value. If the function throws, returns Invalid with the caught error.

Type Parameters​

T​

T

Parameters​

fn​

() => T

Function that may throw

Returns​

Validation<T, unknown>

Validation containing either the return value or the error

Example​

// Parse JSON safely
const parseJSON = <T>(str: string): Validation<T, unknown> =>
  tryCatch(() => JSON.parse(str) as T)

parseJSON('{"name":"John"}')
// => Valid({ name: 'John' })

parseJSON('invalid json')
// => Invalid([SyntaxError: ...])

Call Signature​

tryCatch<T, E>(fn, mapError): Validation<T, E>

Defined in: validation/constructors/index.ts:223

Wraps a potentially throwing function in a Validation with error mapping.

Type Parameters​

T​

T

E​

E

Parameters​

fn​

() => T

Function that may throw

mapError​

(error) => E

Function to transform the caught error

Returns​

Validation<T, E>

Validation containing either the return value or mapped error

Example​

// Parse JSON with custom error
const parseJSON = <T>(str: string): Validation<T, string> =>
  tryCatch(
    () => JSON.parse(str) as T,
    (e) => `JSON parse error: ${e.message}`
  )

// Real-world: Parse with validation
const parseAndValidate = <T>(str: string, validate: Validator<T, T, string>) =>
  pipe(
    tryCatch(() => JSON.parse(str) as T, String),
    flatMap(validate)
  )