Struct ParseError 

pub struct ParseError;

Error returned by <NHSNumber as FromStr>::from_str for any string that is not one of the two accepted shapes (see spec/05-string-forms.md §5).

ParseError is a unit struct — every error value compares equal:

use nhs_number::NHSNumber;
use nhs_number::parse_error::ParseError;
use std::str::FromStr;

let a = NHSNumber::from_str("not even close").unwrap_err();
let b = NHSNumber::from_str("wrong length").unwrap_err();
assert_eq!(a, b);
assert_eq!(a, ParseError);

To map it to your own richer error type:

use nhs_number::NHSNumber;
use std::str::FromStr;

#[derive(Debug, PartialEq)]
enum MyError {
    BadNhsNumber(String),
}

let bad = "not a number";
let result: Result<NHSNumber, MyError> =
    NHSNumber::from_str(bad).map_err(|_| MyError::BadNhsNumber(bad.into()));
assert_eq!(result, Err(MyError::BadNhsNumber("not a number".into())));

ParseError also implements Display and std::error::Error, so it flows through ? into boxed-error stacks without manual mapping:

use nhs_number::NHSNumber;
use std::error::Error;
use std::str::FromStr;

fn parse(s: &str) -> Result<NHSNumber, Box<dyn Error>> {
    Ok(NHSNumber::from_str(s)?)
}

assert!(parse("999 100 0003").is_ok());
assert!(parse("not a number").is_err());

Trait Implementations

impl Debug for ParseError

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for ParseError

A fixed message with no input echo — the rejected candidate string must never leak into error messages or logs (see AGENTS/safety.md §3).

use nhs_number::parse_error::ParseError;

assert_eq!(ParseError.to_string(), "invalid NHS Number string");

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for ParseError

impl Error for ParseError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl PartialEq for ParseError

fn eq(&self, other: &ParseError) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for ParseError