Struct Config

#[non_exhaustive]
pub struct Config {
    pub start_line_number: NonZeroU64,
    pub source: Option<Rc<Source>>,
}

Configuration for the lexer

Config is a builder for the lexer. A new instance is created with default settings. You can then customize the settings by modifying the corresponding fields. Finally, you can pass an input object to the input method to create a lexer.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

start_line_number: NonZeroU64

Line number for the first line of the input

The lexer counts the line number from this value to annotate the location of the tokens. The line number is saved in the start_line_number field of the Code instance that is contained in the Location instance of the token.

The default value is 1.

source: Option<Rc<Source>>

Source of the input

The source is used to annotate the location of the tokens. This value is saved in the source field of the Code instance that is contained in the Location instance of the token.

The default value is None, in which case the source is set to Source::Unknown. It is recommended to set this to a more informative value, so that the locations in the parsed syntax tree can be traced back to the source code. Especially, the correct source is necessary to indicate the location of possible errors that occur during parsing and execution.

Implementations

impl Config

pub fn new() -> Self

Creates a new configuration with default settings.

You can also call Lexer::config to create a new configuration.

pub fn input<'a>(self, input: Box<dyn InputObject + 'a>) -> Lexer<'a>

Creates a lexer with the given input object.

Trait Implementations

impl Debug for Config

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

Formats the value using the given formatter.

impl Default for Config

fn default() -> Self

Returns the “default value” for a type.