Struct Optimizations 

pub struct Optimizations(/* private fields */);

Cell-diff capability flags controlling which optimized escape sequences the screen’s renderer may emit. Re-exported from the renderer so applications can configure rendering with Screen::set_optimizations without depending on renderer internals. Terminal capabilities the renderer may use for shorter output.

Usage

Start from a detector result such as Optimizations::from_env or a baseline such as Optimizations::xterm, then use the with_* methods to toggle assumptions confirmed by probing or terminal-mode setup.

Flag names follow the short capability names used by infocmp where they exist. BS and ONLCR are not terminfo caps; they describe control-character and output-processing behavior.

Implementations

impl Optimizations

pub const ECH: Self

Terminal supports ECH (Erase Characters, CSI Ps X) for clearing a run on the current row.

pub const REP: Self

Terminal supports REP (Repeat preceding character, CSI Ps b) for compact repeated ASCII glyphs.

pub const ICH: Self

Terminal supports ICH (Insert Characters, CSI Ps @) for opening cells within a row.

pub const DCH: Self

Terminal supports DCH (Delete Characters, CSI Ps P) for removing cells within a row.

pub const CSR: Self

Terminal supports scroll regions (DECSTBM; terminfo csr).

pub const SU_SD: Self

Terminal supports SU/SD (Scroll Up/Down, CSI Ps S / CSI Ps T) for moving full scroll regions.

pub const IL_DL: Self

Terminal supports IL/DL (Insert/Delete Line, CSI Ps L / CSI Ps M) for line-level scroll fallbacks.

pub const BCE: Self

Terminal supports BCE (Background Color Erase): erase operations paint with the active background color.

pub const CHA: Self

Terminal supports CHA (Cursor Horizontal Absolute, CSI Ps G) for absolute column moves.

pub const HPA: Self

Terminal supports HPA (Horizontal Position Absolute, `CSI Ps ``) for absolute column moves.

pub const VPA: Self

Terminal supports VPA (Vertical Position Absolute, CSI Ps d) for absolute row moves.

pub const TABS: Self

Literal tab bytes move to configured hardware tab stops.

pub const CBT: Self

Terminal supports CBT (Cursor Backward Tab, CSI Ps Z).

pub const CHT: Self

Terminal supports CHT (Cursor Horizontal Tab, CSI Ps I).

pub const BS: Self

Terminal supports BS (the backspace control character, \x08) for cursor-left-by-one.

pub const ONLCR: Self

Whether the terminal currently maps \n to \r\n (termios ONLCR). In raw mode this is unset and \n only moves the cursor down without resetting the column.

impl Optimizations

pub const fn empty() -> Self

Get a flags value with all bits unset.

pub const fn all() -> Self

Get a flags value with all known bits set.

pub const fn bits(&self) -> u32

Get the underlying bits value.

The returned value is exactly the bits set in this flags value.

pub const fn from_bits(bits: u32) -> Option<Self>

Convert from a bits value.

This method will return None if any unknown bits are set.

pub const fn from_bits_truncate(bits: u32) -> Self

Convert from a bits value, unsetting any unknown bits.

pub const fn from_bits_retain(bits: u32) -> Self

Convert from a bits value exactly.

pub fn from_name(name: &str) -> Option<Self>

Get a flags value with the bits of a flag with the given name set.

This method will return None if name is empty or doesn’t correspond to any named flag.

pub const fn is_empty(&self) -> bool

Whether all bits in self are unset.

pub const fn is_all(&self) -> bool

Whether all known bits in this flags value are set.

pub const fn intersects(&self, other: Self) -> bool

Whether any set bits in other are also set in self.

pub const fn contains(&self, other: Self) -> bool

Whether all set bits in other are also set in self.

pub fn insert(&mut self, other: Self)

The bitwise or (|) of the bits in self and other.

pub fn remove(&mut self, other: Self)

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. remove won’t truncate other, but the ! operator will.

pub fn toggle(&mut self, other: Self)

The bitwise exclusive-or (^) of the bits in self and other.

pub fn set(&mut self, other: Self, value: bool)

Call insert when value is true or remove when value is false.

pub const fn intersection(self, other: Self) -> Self

The bitwise and (&) of the bits in self and other.

pub const fn union(self, other: Self) -> Self

The bitwise or (|) of the bits in self and other.

pub const fn difference(self, other: Self) -> Self

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

pub const fn symmetric_difference(self, other: Self) -> Self

The bitwise exclusive-or (^) of the bits in self and other.

pub const fn complement(self) -> Self

The bitwise negation (!) of the bits in self, truncating the result.

impl Optimizations

pub const fn iter(&self) -> Iter<Optimizations>

Yield a set of contained flags values.

Each yielded flags value will correspond to a defined named flag. Any unknown bits will be yielded together as a final flags value.

pub const fn iter_names(&self) -> IterNames<Optimizations>

Yield a set of contained named flags values.

This method is like iter, except only yields bits in contained named flags. Any unknown bits, or bits not corresponding to a contained flag will not be yielded.

impl Optimizations

pub const fn none() -> Self

Return the most conservative useful capability set.

Every escape-sequence optimization is disabled; only literal hardware tabs and backspace remain enabled. Use this for unknown or genuinely capability-limited terminals when direct cell output is safer than specialized control sequences.

pub const fn modern() -> Self

Return the modern full-feature baseline.

Enables every renderer optimization except Self::ONLCR, since raw mode is the default assumption for terminal applications.

pub const fn xterm() -> Self

Return the xterm-compatible conservative baseline.

Compared to Self::modern, HPA, CHT, and REP are off:

• HPA: konsole and several xterm-compatible terminals lack HPA; xterm-256color terminfo defines HPA via the same sequence as CHA, so CHA is the safer choice.
• CHT: forward-tab support is historically inconsistent across xterm-compatible emulators.
• REP: REP is not universally implemented across the xterm-compatible family.

pub const fn vt100() -> Self

Return the VT100/VT102 baseline.

Predates the xterm extensions for absolute positioning (CHA/HPA/VPA), ECH, REP, BCE, SU/SD, and CBT, but supports DECSTBM, hardware tabs, BS, and on the VT102 the ICH/DCH/IL/DL editing pairs.

pub const fn linux() -> Self

Return the Linux console baseline.

The kernel’s terminal driver implements a narrow subset of ECMA-48 — only absolute positioning (CHA/HPA/VPA), ECH, and ICH on top of the hardware tab stops and BS handled by termios. See console_codes(4).

pub const fn screen() -> Self

Return the GNU screen baseline, derived from infocmp -x1 screen-256color. screen multiplexes onto the host terminal and only re-advertises a conservative subset: no BCE, ECH, REP, CHA, or CHT.

pub const fn with_tabs(self, enabled: bool) -> Self

Return self with hardware tab support (TABS) toggled.

Disable when the receiving terminal is in cooked mode without TAB0 set on c_oflag and \t would otherwise be expanded to spaces.

pub const fn with_bs(self, enabled: bool) -> Self

Return self with backspace-character support (BS) toggled.

Disable when the receiving terminal does not interpret \x08 as cursor-left by one cell.

pub const fn with_onlcr(self, enabled: bool) -> Self

Return self with the \n → \r\n assumption (ONLCR) toggled.

Enable when the terminal is in cooked mode with ONLCR set so a newline both advances a row and resets the column.

pub const fn with_ech(self, enabled: bool) -> Self

Return self with erase-character (ECH) support toggled.

pub const fn with_rep(self, enabled: bool) -> Self

Return self with repeat-character (REP) support toggled.

pub const fn with_ich(self, enabled: bool) -> Self

Return self with insert-character (ICH) support toggled.

pub const fn with_dch(self, enabled: bool) -> Self

Return self with delete-character (DCH) support toggled.

pub const fn with_csr(self, enabled: bool) -> Self

Return self with DECSTBM scroll-region (CSR) support toggled.

pub const fn with_su_sd(self, enabled: bool) -> Self

Return self with scroll-up/scroll-down (SU_SD) support toggled.

pub const fn with_il_dl(self, enabled: bool) -> Self

Return self with insert/delete-line (IL_DL) support toggled.

pub const fn with_bce(self, enabled: bool) -> Self

Return self with background-color-erase (BCE) support toggled.

pub const fn with_cha(self, enabled: bool) -> Self

Return self with cursor-horizontal-absolute (CHA) support toggled.

pub const fn with_hpa(self, enabled: bool) -> Self

Return self with horizontal-position-absolute (HPA) support toggled.

pub const fn with_vpa(self, enabled: bool) -> Self

Return self with vertical-position-absolute (VPA) support toggled.

pub const fn with_cbt(self, enabled: bool) -> Self

Return self with cursor-backward-tab (CBT) support toggled.

pub const fn with_cht(self, enabled: bool) -> Self

Return self with cursor-horizontal-tab (CHT) support toggled.

pub fn from_term(term: &str) -> Self

Derive an optimization set from a TERM value.

Parameters

• term: terminal name, usually from $TERM.

Returns

A baseline capability set for the terminal family. Unknown, empty, and dumb values return Self::none.

pub fn from_env(env: &Env) -> Self

Derive an optimization set from an Env.

Routes $TERM through Self::from_term when it is set, and falls back to Self::default when $TERM is unset entirely. This keeps callers with no environment information (CI harnesses, embedded sinks, tests) on the xterm baseline rather than collapsing to Self::none.

Trait Implementations

impl Binary for Optimizations

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

Formats the value using the given formatter.

impl BitAnd for Optimizations

fn bitand(self, other: Self) -> Self

The bitwise and (&) of the bits in self and other.

type Output = Optimizations

The resulting type after applying the & operator.

impl BitAndAssign for Optimizations

fn bitand_assign(&mut self, other: Self)

The bitwise and (&) of the bits in self and other.

impl BitOr for Optimizations

fn bitor(self, other: Optimizations) -> Self

The bitwise or (|) of the bits in self and other.

type Output = Optimizations

The resulting type after applying the | operator.

impl BitOrAssign for Optimizations

fn bitor_assign(&mut self, other: Self)

The bitwise or (|) of the bits in self and other.

impl BitXor for Optimizations

fn bitxor(self, other: Self) -> Self

The bitwise exclusive-or (^) of the bits in self and other.

type Output = Optimizations

The resulting type after applying the ^ operator.

impl BitXorAssign for Optimizations

fn bitxor_assign(&mut self, other: Self)

The bitwise exclusive-or (^) of the bits in self and other.

impl Clone for Optimizations

fn clone(&self) -> Optimizations

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Optimizations

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

Formats the value using the given formatter.

impl Default for Optimizations

fn default() -> Self

The default is Optimizations::xterm — the modern baseline for the overwhelming majority of terminals reachable from a generic TERM=xterm-256color session.

impl Extend<Optimizations> for Optimizations

fn extend<T: IntoIterator<Item = Self>>(&mut self, iterator: T)

The bitwise or (|) of the bits in each flags value.

fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl Flags for Optimizations

const FLAGS: &'static [Flag<Optimizations>]

The set of defined flags.

type Bits = u32

The underlying bits type.

fn bits(&self) -> u32

Get the underlying bits value.

fn from_bits_retain(bits: u32) -> Optimizations

Convert from a bits value exactly.

fn empty() -> Self

Get a flags value with all bits unset.

fn all() -> Self

Get a flags value with all known bits set.

fn known_bits(&self) -> Self::Bits

Get the known bits from a flags value.

fn unknown_bits(&self) -> Self::Bits

Get the unknown bits from a flags value.

fn contains_unknown_bits(&self) -> bool

This method will return true if any unknown bits are set.

fn from_bits(bits: Self::Bits) -> Option<Self>

Convert from a bits value.

fn from_bits_truncate(bits: Self::Bits) -> Self

Convert from a bits value, unsetting any unknown bits.

fn from_name(name: &str) -> Option<Self>

Get a flags value with the bits of a flag with the given name set.

fn iter(&self) -> Iter<Self>

Yield a set of contained flags values.

fn iter_names(&self) -> IterNames<Self>

Yield a set of contained named flags values.

fn iter_defined_names() -> IterDefinedNames<Self>

Yield a set of all named flags defined by [Self::FLAGS].

fn is_empty(&self) -> bool

Whether all bits in this flags value are unset.

fn is_all(&self) -> bool

Whether all known bits in this flags value are set.

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

where Self: Sized,

Whether any set bits in other are also set in self.

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

where Self: Sized,

Whether all set bits in other are also set in self.

fn truncate(&mut self)

where Self: Sized,

Remove any unknown bits from the flags.

fn insert(&mut self, other: Self)

where Self: Sized,

The bitwise or (|) of the bits in self and other.

fn remove(&mut self, other: Self)

where Self: Sized,

The intersection of self with the complement of other (&!).

fn toggle(&mut self, other: Self)

where Self: Sized,

The bitwise exclusive-or (^) of the bits in self and other.

fn set(&mut self, other: Self, value: bool)

where Self: Sized,

Call [Flags::insert] when value is true or [Flags::remove] when value is false.

fn clear(&mut self)

where Self: Sized,

Unsets all bits in the flags.

fn intersection(self, other: Self) -> Self

The bitwise and (&) of the bits in self and other.

fn union(self, other: Self) -> Self

The bitwise or (|) of the bits in self and other.

fn difference(self, other: Self) -> Self

The intersection of self with the complement of other (&!).

fn symmetric_difference(self, other: Self) -> Self

The bitwise exclusive-or (^) of the bits in self and other.

fn complement(self) -> Self

The bitwise negation (!) of the bits in self, truncating the result.

impl FromIterator<Optimizations> for Optimizations

fn from_iter<T: IntoIterator<Item = Self>>(iterator: T) -> Self

The bitwise or (|) of the bits in each flags value.

impl Hash for Optimizations

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 IntoIterator for Optimizations

type Item = Optimizations

The type of the elements being iterated over.

type IntoIter = Iter<Optimizations>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl LowerHex for Optimizations

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

Formats the value using the given formatter.

impl Not for Optimizations

fn not(self) -> Self

The bitwise negation (!) of the bits in self, truncating the result.

type Output = Optimizations

The resulting type after applying the ! operator.

impl Octal for Optimizations

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

Formats the value using the given formatter.

impl PartialEq for Optimizations

fn eq(&self, other: &Optimizations) -> 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 PublicFlags for Optimizations

type Primitive = u32

The type of the underlying storage.

type Internal = InternalBitFlags

The type of the internal field on the generated flags type.

impl Sub for Optimizations

fn sub(self, other: Self) -> Self

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

type Output = Optimizations

The resulting type after applying the - operator.

impl SubAssign for Optimizations

fn sub_assign(&mut self, other: Self)

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

impl UpperHex for Optimizations

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

Formats the value using the given formatter.

impl Copy for Optimizations

impl Eq for Optimizations

impl StructuralPartialEq for Optimizations