Struct TextRange 

pub struct TextRange {
    pub start: usize,
    pub end: usize,
}

Represents a range in text, used for cursor position and selection.

When start == end, this represents a cursor position (collapsed selection). When start != end, this represents a text selection.

Invariants

• Indices are in UTF-8 byte offsets (matching Rust’s String)
• start can be greater than end for reverse selections
• Use min() and max() for ordered access

Fields

start: usize

Start index of the range (can be > end for reverse selection)

end: usize

End index of the range

Implementations

impl TextRange

pub const fn new(start: usize, end: usize) -> Self

Creates a new text range.

pub const fn cursor(position: usize) -> Self

Creates a collapsed range (cursor) at the given position.

pub const fn zero() -> Self

Creates a range from 0 to 0 (cursor at start).

pub const fn collapsed(&self) -> bool

Returns true if this range is collapsed (cursor, not selection).

pub fn length(&self) -> usize

Returns the length of the selection in characters.

pub fn min(&self) -> usize

Returns the minimum (leftmost) index.

pub fn max(&self) -> usize

Returns the maximum (rightmost) index.

pub fn contains(&self, index: usize) -> bool

Returns true if this range contains the given index.

pub fn coerce_in(&self, max: usize) -> Self

Coerces the range to be within [0, max].

pub const fn all(length: usize) -> Self

Returns a range covering the entire text of given length.

pub fn safe_slice<'a>(&self, text: &'a str) -> &'a str

Safely slices the text, clamping to valid UTF-8 char boundaries.

This handles edge cases where:

• Range extends beyond text length
• Range indices are not on char boundaries (e.g., in middle of multi-byte UTF-8)

Returns an empty string if the range is invalid.

Trait Implementations

impl Clone for TextRange

fn clone(&self) -> TextRange

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TextRange

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

Formats the value using the given formatter.

impl Default for TextRange

fn default() -> TextRange

Returns the “default value” for a type.

impl Hash for TextRange

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 TextRange

fn eq(&self, other: &TextRange) -> 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 Copy for TextRange

impl Eq for TextRange

impl StructuralPartialEq for TextRange