Struct NarjuHelper 

pub struct NarjuHelper {
    pub completer: FilenameCompleter,
    pub hinter: HistoryHinter,
}

The rustyline helper for the raw λ↑↓ REPL: syntax highlighting, filename completion (for :load), history hints, and bracket validation.

Fields

completer: FilenameCompleter

Completes filenames, for :load arguments.

hinter: HistoryHinter

Offers the rest of a matching history entry as a dimmed hint.

Trait Implementations

impl Completer for NarjuHelper

type Candidate = <FilenameCompleter as Completer>::Candidate

Specific completion candidate.

fn complete( &self, line: &str, pos: usize, ctx: &Context<'_>, ) -> Result<(usize, Vec<Self::Candidate>)>

Takes the currently edited line with the cursor position and returns the start position and the completion candidates for the partial word to be completed.

fn update( &self, line: &mut LineBuffer, start: usize, elected: &str, cl: &mut Changeset, )

Updates the edited line with the elected candidate.

impl Highlighter for NarjuHelper

fn highlight_hint<'h>(&self, hint: &'h str) -> Cow<'h, str>

Takes the hint and returns the highlighted version (with ANSI color).

fn highlight_prompt<'b, 's: 'b, 'p: 'b>( &'s self, prompt: &'p str, _default: bool, ) -> Cow<'b, str>

Takes the prompt and returns the highlighted version (with ANSI color).

fn highlight<'l>(&self, line: &'l str, pos: usize) -> Cow<'l, str>

Takes the currently edited line with the cursor position and returns the highlighted version (with ANSI color).

fn highlight_char(&self, _line: &str, _pos: usize, _forced: bool) -> bool

Tells if line needs to be highlighted when a specific char is typed or when cursor is moved under a specific char. forced flag is true mainly when user presses Enter (i.e. transient vs final highlight).

fn highlight_candidate<'c>( &self, candidate: &'c str, completion: CompletionType, ) -> Cow<'c, str>

Takes the completion candidate and returns the highlighted version (with ANSI color).

impl Hinter for NarjuHelper

type Hint = <HistoryHinter as Hinter>::Hint

Specific hint type

fn hint(&self, line: &str, pos: usize, ctx: &Context<'_>) -> Option<Self::Hint>

Takes the currently edited line with the cursor position and returns the string that should be displayed or None if no hint is available for the text the user currently typed.

impl Validator for NarjuHelper

Bracket-balance validator — waits for balanced parens before submitting.

fn validate(&self, ctx: &mut ValidationContext<'_>) -> Result<ValidationResult>

Takes the currently edited input and returns a ValidationResult indicating whether it is valid or not along with an option message to display about the result. The most common validity check to implement is probably whether the input is complete or not, for instance ensuring that all delimiters are fully balanced.

fn validate_while_typing(&self) -> bool

Configure whether validation is performed while typing or only when user presses the Enter key.

impl Helper for NarjuHelper