lexical-parse-float 0.8.5

Efficient parsing of floats from strings.
Documentation 
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use lexical_parse_float::number::Number;
use lexical_util::format::STANDARD;

#[test]
fn is_fast_path_test() {
    let mut number = Number {
        exponent: -4,
        mantissa: 12345,
        is_negative: false,
        many_digits: false,
        integer: &[],
        fraction: None,
    };
    assert_eq!(number.is_fast_path::<f32, { STANDARD }>(), true);
    assert_eq!(number.is_fast_path::<f64, { STANDARD }>(), true);

    number.exponent = -15;
    assert_eq!(number.is_fast_path::<f32, { STANDARD }>(), false);
    assert_eq!(number.is_fast_path::<f64, { STANDARD }>(), true);

    number.exponent = -25;
    assert_eq!(number.is_fast_path::<f32, { STANDARD }>(), false);
    assert_eq!(number.is_fast_path::<f64, { STANDARD }>(), false);

    number.exponent = 25;
    assert_eq!(number.is_fast_path::<f32, { STANDARD }>(), false);
    assert_eq!(number.is_fast_path::<f64, { STANDARD }>(), true);

    number.exponent = 36;
    assert_eq!(number.is_fast_path::<f32, { STANDARD }>(), false);
    assert_eq!(number.is_fast_path::<f64, { STANDARD }>(), true);

    number.exponent = 38;
    assert_eq!(number.is_fast_path::<f32, { STANDARD }>(), false);
    assert_eq!(number.is_fast_path::<f64, { STANDARD }>(), false);

    number.mantissa = 1 << 25;
    number.exponent = 0;
    assert_eq!(number.is_fast_path::<f32, { STANDARD }>(), false);
    assert_eq!(number.is_fast_path::<f64, { STANDARD }>(), true);

    number.mantissa = 1 << 54;
    assert_eq!(number.is_fast_path::<f32, { STANDARD }>(), false);
    assert_eq!(number.is_fast_path::<f64, { STANDARD }>(), false);

    number.mantissa = 1 << 52;
    assert_eq!(number.is_fast_path::<f32, { STANDARD }>(), false);
    assert_eq!(number.is_fast_path::<f64, { STANDARD }>(), true);

    number.many_digits = true;
    assert_eq!(number.is_fast_path::<f32, { STANDARD }>(), false);
    assert_eq!(number.is_fast_path::<f64, { STANDARD }>(), false);
}

#[test]
fn try_fast_path_test() {
    let mut number = Number {
        exponent: -4,
        mantissa: 12345,
        is_negative: false,
        many_digits: false,
        integer: &[],
        fraction: None,
    };
    assert_eq!(number.try_fast_path::<f32, { STANDARD }>(), Some(1.2345));
    assert_eq!(number.try_fast_path::<f64, { STANDARD }>(), Some(1.2345));

    number.exponent = -10;
    assert_eq!(number.try_fast_path::<f32, { STANDARD }>(), Some(1.2345e-6));
    assert_eq!(number.try_fast_path::<f64, { STANDARD }>(), Some(1.2345e-6));

    number.exponent = -20;
    assert_eq!(number.try_fast_path::<f32, { STANDARD }>(), None);
    assert_eq!(number.try_fast_path::<f64, { STANDARD }>(), Some(1.2345e-16));

    number.exponent = -25;
    assert_eq!(number.try_fast_path::<f32, { STANDARD }>(), None);
    assert_eq!(number.try_fast_path::<f64, { STANDARD }>(), None);

    number.exponent = 12;
    assert_eq!(number.try_fast_path::<f32, { STANDARD }>(), Some(1.2345e16));
    assert_eq!(number.try_fast_path::<f64, { STANDARD }>(), Some(1.2345e16));

    number.exponent = 25;
    assert_eq!(number.try_fast_path::<f32, { STANDARD }>(), None);
    assert_eq!(number.try_fast_path::<f64, { STANDARD }>(), Some(1.2345e29));

    number.exponent = 32;
    assert_eq!(number.try_fast_path::<f32, { STANDARD }>(), None);
    assert_eq!(number.try_fast_path::<f64, { STANDARD }>(), Some(1.2345e36));

    number.exponent = 36;
    assert_eq!(number.try_fast_path::<f32, { STANDARD }>(), None);
    assert_eq!(number.try_fast_path::<f64, { STANDARD }>(), None);
}