pub trait FromBStr: Sized {
type Err;
// Required method
fn from_bstr(s: &[u8]) -> Result<Self, Self::Err>;
}Expand description
Parse a value from a string
FromBStr’s from_bstr method is often used implicitly, through
[u8]’s parse method. See parse’s documentation for examples.
FromBStr does not have a lifetime parameter, and so you can only parse types
that do not contain a lifetime parameter themselves. In other words, you can
parse an i32 with FromBStr, but not a &i32. You can parse a struct that
contains an i32, but not one that contains an &i32.
§Examples
Basic implementation of FromBStr on an example Point type:
use bstr_parse::*;
#[derive(Debug, PartialEq)]
struct Point {
x: i32,
y: i32
}
impl FromBStr for Point {
type Err = ParseIntError;
fn from_bstr(s: &[u8]) -> Result<Self, Self::Err> {
let coords: Vec<&[u8]> = s.split(|&p| p == b'(' || p == b')' || p == b',')
.skip_while(|s| s.is_empty())
.take_while(|s| !s.is_empty())
.collect();
let x_frombstr = coords[0].parse::<i32>()?;
let y_frombstr = coords[1].parse::<i32>()?;
Ok(Point { x: x_frombstr, y: y_frombstr })
}
}
let p = Point::from_bstr(b"(1,2)");
assert_eq!(p.unwrap(), Point{ x: 1, y: 2} )Required Associated Types§
Required Methods§
Sourcefn from_bstr(s: &[u8]) -> Result<Self, Self::Err>
fn from_bstr(s: &[u8]) -> Result<Self, Self::Err>
Parses a string s to return a value of this type.
If parsing succeeds, return the value inside Ok, otherwise
when the string is ill-formatted return an error specific to the
inside Err. The error type is specific to implementation of the trait.
§Examples
Basic usage with i32, a type that implements FromBStr:
use bstr_parse::*;
let s = b"5";
let x = i32::from_bstr(s).unwrap();
assert_eq!(5, x);Dyn Compatibility§
This trait is not dyn compatible.
In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.