CSOSN

Validate

• JavaScript library
• Python library
• Go library1 case fails
• Ruby library
• Rust library1 case fails
• .NET library
• Erlang library

Checks whether a CSOSN is one of the 10 codes of the official table: 101, 102, 103, 201, 202, 203, 300, 400, 500, 900.

• Accepts the bare 3 digits as a string, or a non-negative integer. A CSOSN has no printed grouping, so the function rejects a masked value.
• Surrounding whitespace is ignored. Any other string is rejected: the function does not pick out its digits ("abc101").
• Nothing is padded: no code starts with a zero, so a value narrower than 3 digits is not a code. A number is read only when it is a safe non-negative integer.
• No behavior change in 2.5.0.
• Source: Anexo III-A of Convênio SINIEF s/nº 1970 (table instituted by Ajuste SINIEF 03/2010).

import { isValidCsosn } from '@brazilian-utils/brazilian-utils';

isValidCsosn('101'); // true
isValidCsosn(900); // true
isValidCsosn('999'); // false
isValidCsosn('abc101'); // false (not a documented form)
isValidCsosn(-101); // false (not a non-negative safe integer)