Crate reformation
source ·Expand description
Parsing via regular expressions using format syntax
Deriving trait Reformation
will also implement
trait FromStr
, with Err=Box<Error>
Derive will require attribute reformation to specify format string, which will be treated as format string -> regular expression string
Types implementing Reformation
by default:
- signed integers:
i8
i16
i32
i64
i128
isize
- unsigned integers:
u8
u16
u32
u64
u128
usize
- floats:
f32
f64
String
use reformation::Reformation;
#[derive(Reformation, Debug)]
#[reformation(r"{year}-{month}-{day} {hour}:{minute}")]
struct Date{
year: u16,
month: u8,
day: u8,
hour: u8,
minute: u8,
}
fn main(){
let date: Date = "2018-12-22 20:23".parse().unwrap();
assert_eq!(date.year, 2018);
assert_eq!(date.month, 12);
assert_eq!(date.day, 22);
assert_eq!(date.hour, 20);
assert_eq!(date.minute, 23);
}
Format string behaves as regular expression, so special symbols needs to be escaped.
Also they can be used for more flexible format strings.
AVOID capture groups, since they would mess up with indexing of capture group
generated by macro. use non-capturing groups r"(?:)"
instead.
use reformation::Reformation;
// '{' is special symbol in both format and regex syntax, so it must be escaped twice.
// Say hello to good old escape hell. Good thing its only one.
#[derive(Reformation, Debug)]
#[reformation(r"Vec\{{{x},\s*{y},\s*{z}\}}")]
struct Vec{
x: f64,
y: f64,
z: f64,
}
fn main(){
// spaces between coordinates does not matter, since any amount of spaces
// matches to r"\s*"
let v: Vec = "Vec{-0.4,1e-3, 2e-3}".parse().unwrap();
assert_eq!(v.x, -0.4);
assert_eq!(v.y, 0.001);
assert_eq!(v.z, 0.002);
}
Macros
Creates function for parsing tuple of values from
strings corresponding to given template.
Structs
Captures represents a group of captured strings for a single match.
A compiled regular expression for matching Unicode strings.