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use crate::num::dec2flt::rawfp::RawFloat;
use crate::num::FpCategory;
use crate::{f32, f64};
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub struct Decoded {
    
    pub mant: u64,
    
    pub minus: u64,
    
    pub plus: u64,
    
    pub exp: i16,
    
    
    
    pub inclusive: bool,
}
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub enum FullDecoded {
    
    Nan,
    
    Infinite,
    
    Zero,
    
    Finite(Decoded),
}
pub trait DecodableFloat: RawFloat + Copy {
    
    fn min_pos_norm_value() -> Self;
}
impl DecodableFloat for f32 {
    fn min_pos_norm_value() -> Self {
        f32::MIN_POSITIVE
    }
}
impl DecodableFloat for f64 {
    fn min_pos_norm_value() -> Self {
        f64::MIN_POSITIVE
    }
}
pub fn decode<T: DecodableFloat>(v: T) -> ( bool, FullDecoded) {
    let (mant, exp, sign) = v.integer_decode();
    let even = (mant & 1) == 0;
    let decoded = match v.classify() {
        FpCategory::Nan => FullDecoded::Nan,
        FpCategory::Infinite => FullDecoded::Infinite,
        FpCategory::Zero => FullDecoded::Zero,
        FpCategory::Subnormal => {
            
            
            
            FullDecoded::Finite(Decoded { mant, minus: 1, plus: 1, exp, inclusive: even })
        }
        FpCategory::Normal => {
            let minnorm = <T as DecodableFloat>::min_pos_norm_value().integer_decode();
            if mant == minnorm.0 {
                
                
                FullDecoded::Finite(Decoded {
                    mant: mant << 2,
                    minus: 1,
                    plus: 2,
                    exp: exp - 2,
                    inclusive: even,
                })
            } else {
                
                FullDecoded::Finite(Decoded {
                    mant: mant << 1,
                    minus: 1,
                    plus: 1,
                    exp: exp - 1,
                    inclusive: even,
                })
            }
        }
    };
    (sign < 0, decoded)
}