DoubleWidth as in-memory words

[oscbyspro]

Hm. I think DoubleWidth would be much simpler if it were stored in words order.

/// In words order:

public var low:  Low
public var high: High

/// In platform endianness order:

#if _endian(big)

public var high: High
public var low:  Low

#else

public var low:  Low
public var high: High

#endif

---

Pros

• I could remove most or all #if _endian(...) stuff.
• I could remove TwinHeaded<Base> from the project.
• withContigous[Mutable]Storage(_:) is made viable.
• Unsafe initialization is easier.

Cons

• Unsafe non-UInt chunking is trickier.
• Unsafe serialization (without .bigEndian) is trickier.

[oscbyspro]

Somebody, please ban big endianness. Such headache. No benefit.

[oscbyspro]

But is it possible to implement var byteSwapped: Self in words order? What would it do on big-endian platforms? Looking at littleEndian's and bigEndian's documentation

If necessary, the byte order of this value is reversed from the typical byte order of this integer type. On a little-endian platform, for any integer x, x == x.littleEndian.

If necessary, the byte order of this value is reversed from the typical byte order of this integer type. On a big-endian platform, for any integer x, x == x.bigEndian.

it seems like they require platform-endian in-memory representations (which I have). Hm.

[oscbyspro]

Again: somebody, please ban big endianness. Such headache. No benefit.