Struct DcgRule 

pub struct DcgRule {
    pub lhs: PrologTerm,
    pub rhs: Vec<DcgRhs>,
    pub guards: Vec<PrologTerm>,
    pub comment: Option<String>,
}

A DCG (Definite Clause Grammar) rule: lhs --> rhs.

Fields

lhs: PrologTerm

Left-hand side nonterminal.

rhs: Vec<DcgRhs>

Right-hand side: sequence of nonterminals, terminals [token], and pushback notation.

guards: Vec<PrologTerm>

Optional Prolog goals in {...}.

comment: Option<String>

Optional comment.

Implementations

impl DcgRule

pub fn emit(&self) -> String

Emit this DCG rule as a Prolog string.

Trait Implementations

impl Clone for DcgRule

fn clone(&self) -> DcgRule

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DcgRule

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

Formats the value using the given formatter.

impl PartialEq for DcgRule

fn eq(&self, other: &DcgRule) -> 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 StructuralPartialEq for DcgRule