partiql-eval 0.14.0

mod base_table;
pub(crate) use base_table::*;
mod coll;
pub(crate) use coll::*;
mod control_flow;
pub(crate) use control_flow::*;
mod data_types;
pub(crate) use data_types::*;
mod datetime;
pub(crate) use datetime::*;
mod strings;
pub(crate) use strings::*;
mod path;
pub(crate) use path::*;
mod pattern_match;
pub(crate) use pattern_match::*;

mod graph_match;
pub(crate) use graph_match::*;
mod functions;
mod operators;

pub(crate) use operators::*;

use crate::eval::EvalContext;

use partiql_value::datum::{DatumLowerError, RefTupleView};
use partiql_value::Value;
use std::borrow::Cow;
use std::fmt::Debug;
use thiserror::Error;

/// A trait for expressions that require evaluation, e.g. `a + b` or `c > 2`.
pub trait EvalExpr: Debug {
    fn evaluate<'a, 'c, 'o>(
        &'a self,
        bindings: &'a dyn RefTupleView<'a, Value>,
        ctx: &'c dyn EvalContext,
    ) -> Cow<'o, Value>
    where
        'c: 'a,
        'a: 'o;
}

#[derive(Error, Debug)]
#[non_exhaustive]
/// An error in binding an expression for evaluation
pub enum BindError {
    #[error("Argument number mismatch: expected one of `{expected:?}`, found `{found}` ")]
    ArgNumMismatch { expected: Vec<usize>, found: usize },

    /// Feature has not yet been implemented.
    #[error("Argument constraint not satisfied: `{0}`")]
    ArgumentConstraint(String),

    /// Feature has not yet been implemented.
    #[error("Not yet implemented: {0}")]
    NotYetImplemented(String),

    #[error("Error lowering literal value: {0}")]
    LiteralValue(#[from] DatumLowerError),

    /// Any other error.
    #[error("Bind error: unknown error")]
    Unknown,
}

/// A trait for binding an expression to its arguments into an `EvalExpr`
pub trait BindEvalExpr: Debug {
    fn bind<const STRICT: bool>(
        self,
        args: Vec<Box<dyn EvalExpr>>,
    ) -> Result<Box<dyn EvalExpr>, BindError>;
}