Enum WcharWidth 

pub enum WcharWidth {
    Two,
    Four,
}

How many bytes one Char16 occupies on the wire.

XTypes 1.3 §7.4.1.1.1, Table 31 says two, and two of the three measured implementations write two everywhere. RTI Connext 7.7 writes four under XCDR1 — measured 2026-08-09 with @final struct WCh { wchar c; octet tail; }, c = U+0061: RTI’s XCDR1 payload is 61000000 ab little endian and 00000061 ab big endian, against 6100 ab / 0061 ab from Cyclone, Fast DDS and RTI’s own XCDR2. It is the same character width RTI’s XCDR1 wstring uses, which is why the two are one setting and not two — zerodds_ast_layout::WstringLengthPolicy::character_width is where the width is chosen, and this enum is how it reaches the byte layer.

A width is not a formatting difference. A wchar read two bytes wide out of a four-byte field returns the wrong character and leaves every member after it two bytes out of place.

Variants

Two

Two bytes, one UTF-16 code unit. Table 31, and what three of the four measured (vendor, encoding version) pairs write.

Four

Four bytes, one UTF-16 code unit zero-extended. RTI Connext under XCDR1.

Implementations

impl WcharWidth

pub const fn bytes(self) -> usize

The width in bytes, which is also the alignment under WcharFraming::Fixed: a Char16 is a primitive and aligns to its own size, capped by MAXALIGN. Under WcharFraming::GiopLengthPrefixed it is the count in the leading octet and the alignment is one.

Trait Implementations

impl Clone for WcharWidth

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for WcharWidth

impl Debug for WcharWidth

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for WcharWidth

fn default() -> Self

Returns the “default value” for a type.

impl Eq for WcharWidth

impl PartialEq for WcharWidth

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for WcharWidth