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#[macro_use]
extern crate nom;
use nom::digit;
use nom::types::CompleteStr;
#[macro_export]
macro_rules! complete_named (
($name:ident, $submac:ident!( $($args:tt)* )) => (
fn $name( i: CompleteStr ) -> nom::IResult<CompleteStr, CompleteStr, u32> {
$submac!(i, $($args)*)
}
);
($name:ident<$o:ty>, $submac:ident!( $($args:tt)* )) => (
fn $name( i: CompleteStr ) -> nom::IResult<CompleteStr, $o, u32> {
$submac!(i, $($args)*)
}
);
);
complete_named!(
unsigned_float<f32>,
flat_map!(
recognize!(alt!(
delimited!(digit, tag!("."), opt!(digit)) | delimited!(opt!(digit), tag!("."), digit)
)),
parse_to!(f32)
)
);
complete_named!(
float<f32>,
map!(
pair!(opt!(alt!(tag!("+") | tag!("-"))), unsigned_float),
|(sign, value): (Option<CompleteStr>, f32)| sign
.and_then(|s| s.0.chars().next())
.and_then(|c| if c == '-' { Some(-1f32) } else { None })
.unwrap_or(1f32) * value
)
);
#[test]
fn unsigned_float_test() {
assert_eq!(
unsigned_float(CompleteStr("123.456")),
Ok((CompleteStr(""), 123.456))
);
assert_eq!(
unsigned_float(CompleteStr("0.123")),
Ok((CompleteStr(""), 0.123))
);
assert_eq!(
unsigned_float(CompleteStr("123.0")),
Ok((CompleteStr(""), 123.0))
);
assert_eq!(
unsigned_float(CompleteStr("123.")),
Ok((CompleteStr(""), 123.0))
);
assert_eq!(
unsigned_float(CompleteStr(".123")),
Ok((CompleteStr(""), 0.123))
);
}
#[test]
fn float_test() {
assert_eq!(
float(CompleteStr("123.456")),
Ok((CompleteStr(""), 123.456))
);
assert_eq!(
float(CompleteStr("+123.456")),
Ok((CompleteStr(""), 123.456))
);
assert_eq!(
float(CompleteStr("-123.456")),
Ok((CompleteStr(""), -123.456))
);
}
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