Struct ProviderChain 

pub struct ProviderChain(pub Vec<FormatProvider>);

An ordered list of providers for one intent.

Written comma-separated: :set format.reformat=lsp,lang-default.

A command line in an external: rung may not contain a comma — the comma is the chain separator and there is no escape. This is a deliberate limit rather than an oversight: the alternative is a quoting grammar inside a :set value, which is a lot of machinery for a case (--config a,b) that a one-line wrapper script solves. The error message says so when it bites.

Tuple Fields

0: Vec<FormatProvider>

Implementations

impl ProviderChain

pub fn new(providers: Vec<FormatProvider>) -> Self

A chain trying providers in order. An empty vector is a valid “this intent does nothing” chain (see Self::parse).

pub fn of(provider: FormatProvider) -> Self

The single-provider chain, for the common defaults.

pub fn iter(&self) -> Iter<'_, FormatProvider>

The providers in resolution order — first available wins.

pub fn is_empty(&self) -> bool

Whether the chain names no provider at all (the user switched the intent off).

pub fn len(&self) -> usize

Number of providers in the chain.

pub fn label(&self) -> String

Canonical string form. Round-trips with Self::parse.

pub fn parse(s: &str) -> Result<Self, String>

Parse a comma-separated chain.

The empty string is a valid EMPTY chain, not an error: it is how a user says “this intent does nothing here”, and rejecting it would leave no way to express that short of a sentinel value. An empty chain reports “nothing configured” at resolution rather than falling back to a default the user just removed.

Errors

A human-readable message for an empty entry (lsp,,native) or any rung FormatProvider::parse rejects.

Examples

use lattice_core::{FormatProvider, ProviderChain};

let chain = ProviderChain::parse("lsp, external:prettier --stdin-filepath %")
    .unwrap_or_default();
assert_eq!(
    chain.iter().cloned().collect::<Vec<_>>(),
    [
        FormatProvider::Lsp,
        FormatProvider::External("prettier --stdin-filepath %".into()),
    ],
);
assert_eq!(chain.label(), "lsp,external:prettier --stdin-filepath %");

assert!(ProviderChain::parse("").is_ok_and(|c| c.is_empty()));
assert!(ProviderChain::parse("nativ").is_err()); // typo, not a program

Trait Implementations

impl Clone for ProviderChain

fn clone(&self) -> ProviderChain

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ProviderChain

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

Formats the value using the given formatter.

impl Default for ProviderChain

fn default() -> ProviderChain

Returns the “default value” for a type.

impl Display for ProviderChain

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

Formats the value using the given formatter.

impl Eq for ProviderChain

impl PartialEq for ProviderChain

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ProviderChain