Enum WidthSpec 

#[non_exhaustive]
pub enum WidthSpec {
    Auto,
    Fixed(u32),
    Pct(u8),
    Ratio(u16, u16),
    MinMax {
        min: u32,
        max: u32,
    },
}

Width specification for a flexbox item.

Replaces the previous trio of Option-typed fields (min_width, max_width, width_pct) with a single tagged enum. Resolution at layout time dispatches on the variant.

Constraints::default() produces WidthSpec::Auto.

Variant semantics

• Auto — no width constraint; the element sizes from content and available space.
• Fixed(n) — exact cell width. Equivalent to MinMax { min: Some(n), max: Some(n) }.
• Pct(p) — percentage of parent width (clamped to 0..=100).
• Ratio(num, den) — exact integer fraction. For example Ratio(1, 3) produces area / 3. Floor division: area = 80, num = 1, den = 3 → 26. A den of 0 is treated as no constraint.
• MinMax { min, max } — bounds on each side independently.

Example

use slt::{Constraints, WidthSpec};

let c = Constraints::default().w_ratio(1, 3);
assert_eq!(c.width, WidthSpec::Ratio(1, 3));

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Auto

Unconstrained — sizes from content and available space.

Fixed(u32)

Exact cell width.

Pct(u8)

Percentage of parent width (0..=100).

Ratio(u16, u16)

Exact integer fraction of parent (numerator, denominator).

Ratio(1, 3) produces area / 3. Floor division — for area = 80, num = 1, den = 3 → 26. A den of 0 is treated as no constraint.

MinMax

Min and/or max bounds. Sentinels are used so that the variant fits in 12 bytes (24 bytes total for the two-axis Constraints struct):

• min = 0 means “no minimum” (equivalent to Option::None); since a min of 0 is the same as no minimum, using 0 as the sentinel does not lose any expressible state.
• max = u32::MAX means “no maximum” (the natural infinity).

Use the Constraints::min_w / Constraints::max_w / Constraints::w_minmax builders to construct this variant without thinking about sentinels.

Fields

min: u32

Minimum width. 0 means unbounded below.

max: u32

Maximum width. u32::MAX means unbounded above.

Trait Implementations

impl Clone for WidthSpec

fn clone(&self) -> WidthSpec

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for WidthSpec

impl Debug for WidthSpec

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

Formats the value using the given formatter.

impl Default for WidthSpec

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for WidthSpec

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for WidthSpec

impl Hash for WidthSpec

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for WidthSpec

fn eq(&self, other: &WidthSpec) -> 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 Serialize for WidthSpec

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for WidthSpec