Struct StringLayout 

pub struct StringLayout {
    pub len_offset: usize,
    pub data_offset: usize,
    pub is_sso: bool,
    pub sso_max_len: usize,
    pub sso_total_size: usize,
}

Memory layout for a string object.

OxiLean strings are heap-allocated objects with a reference count header, a length field, and an inline (or pointer-to) UTF-8 byte array.

+--------+---------+--------+---------+----------+
| RC (8) | Tag (1) | Flags  | Len (4) | Data ... |
+--------+---------+--------+---------+----------+

Fields

len_offset: usize

Byte offset of the length field.

data_offset: usize

Byte offset of the UTF-8 data.

is_sso: bool

Whether the string is SSO (short-string optimized / inline).

sso_max_len: usize

Maximum length for SSO strings.

sso_total_size: usize

Total allocated size for an SSO string (fixed).

Implementations

impl StringLayout

pub fn standard() -> Self

Standard (non-SSO) string layout.

pub fn sso(max_len: usize) -> Self

Short-string-optimized layout (inline up to max_len bytes).

pub fn alloc_size(&self, str_len: usize) -> usize

Compute the total allocation size for a given string length.

Trait Implementations

impl Clone for StringLayout

fn clone(&self) -> StringLayout

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for StringLayout

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

Formats the value using the given formatter.

impl Display for StringLayout

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

Formats the value using the given formatter.

impl PartialEq for StringLayout

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for StringLayout

impl StructuralPartialEq for StringLayout