/std

@thourum/fault/std provides small Result wrappers for JSON, files, and environment variables.

safeJsonParse

safeJsonParse<T = unknown>(text: string): Result<T, Fault>

const config = safeJsonParse<Config>(text)
config.match(useConfig, handleFault)

safeJsonParse returns the parsed value or preserves the thrown cause with JSON.parse failed details.

Tag produced: PARSE_ERROR.

safeJsonStringify(value: unknown, space?: number): Result<string, Fault>

const json = safeJsonStringify({ enabled: true }, 2)
json.match(writeConfig, handleFault)

safeJsonStringify treats circular values, BigInt, and an undefined JSON result as parse faults with JSON.stringify failed details.

Tag produced: PARSE_ERROR.

safeReadFile(path: string, encoding: BufferEncoding = 'utf8'): ResultAsync<string, Fault>

const contents = await safeReadFile('./config.json')
contents.match(useContents, handleFault)

safeReadFile records the file path and error code in metadata and maps filesystem codes with the table below.

Tags produced: NOT_FOUND, FORBIDDEN, or INTERNAL_ERROR.

safeWriteFile(path: string, data: string | Uint8Array): ResultAsync<void, Fault>

const saved = await safeWriteFile('./output.json', text)
saved.match(onSaved, handleFault)

safeWriteFile uses the same filesystem tag mapping and metadata as safeReadFile.

Tags produced: NOT_FOUND, FORBIDDEN, or INTERNAL_ERROR.

safeEnv(name: string): Result<string, Fault>

const databaseUrl = safeEnv('DATABASE_URL')
databaseUrl.match(connect, handleFault)

safeEnv rejects missing and empty variables, including the variable name in metadata.

Tag produced: CONFIGURATION_ERROR.