You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

47 lines
1.2 KiB

#[macro_use]
extern crate nom;
use nom::character::streaming::digit1 as digit;
use std::str;
use std::str::FromStr;
named!(
unsigned_float<f32>,
map_res!(
map_res!(
recognize!(alt!(
delimited!(digit, tag!("."), opt!(digit)) | delimited!(opt!(digit), tag!("."), digit)
)),
str::from_utf8
),
FromStr::from_str
)
);
named!(
float<f32>,
map!(
pair!(opt!(alt!(tag!("+") | tag!("-"))), unsigned_float),
|(sign, value): (Option<&[u8]>, f32)| sign
.and_then(|s| if s[0] == b'-' { Some(-1f32) } else { None })
.unwrap_or(1f32) * value
)
);
#[test]
fn unsigned_float_test() {
assert_eq!(unsigned_float(&b"123.456;"[..]), Ok((&b";"[..], 123.456)));
assert_eq!(unsigned_float(&b"0.123;"[..]), Ok((&b";"[..], 0.123)));
assert_eq!(unsigned_float(&b"123.0;"[..]), Ok((&b";"[..], 123.0)));
assert_eq!(unsigned_float(&b"123.;"[..]), Ok((&b";"[..], 123.0)));
assert_eq!(unsigned_float(&b".123;"[..]), Ok((&b";"[..], 0.123)));
}
#[test]
fn float_test() {
assert_eq!(float(&b"123.456;"[..]), Ok((&b";"[..], 123.456)));
assert_eq!(float(&b"+123.456;"[..]), Ok((&b";"[..], 123.456)));
assert_eq!(float(&b"-123.456;"[..]), Ok((&b";"[..], -123.456)));
}