plotnik-bytecode 0.3.2

Bytecode format and runtime types for Plotnik
Documentation 
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//! Quantifier kinds for type inference.
//!
//! Quantifiers determine cardinality: how many times a pattern can match.

/// Quantifier kind for pattern matching.
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum QuantifierKind {
    /// `?` or `??` - zero or one.
    Optional,
    /// `*` or `*?` - zero or more.
    ZeroOrMore,
    /// `+` or `+?` - one or more.
    OneOrMore,
}

impl QuantifierKind {
    /// Whether this quantifier requires strict dimensionality (row capture).
    ///
    /// `*` and `+` produce arrays, so internal captures need explicit row structure.
    /// `?` produces at most one value, so no dimensionality issue.
    pub fn requires_row_capture(self) -> bool {
        matches!(self, Self::ZeroOrMore | Self::OneOrMore)
    }

    /// Whether this quantifier guarantees at least one match.
    pub fn is_non_empty(self) -> bool {
        matches!(self, Self::OneOrMore)
    }

    /// Whether this quantifier can match zero times.
    pub fn can_be_empty(self) -> bool {
        matches!(self, Self::Optional | Self::ZeroOrMore)
    }
}