Enum Returning 

pub enum Returning {
    Model {
        include: Vec<Path>,
    },
    Changed,
    Expr(Expr),
    Value(Expr),
}

Specifies what data a statement returns.

Used both as the projection in SELECT queries and as the RETURNING clause in INSERT, UPDATE, and DELETE statements.

Examples

use toasty_core::stmt::Returning;

let ret = Returning::Model { include: vec![] };
assert!(ret.is_model());

Variants

Model

Return the full model with the specified association includes.

Fields

include: Vec<Path>

Paths to associations that should be eagerly loaded.

Changed

Return whether the operation changed any rows.

Expr(Expr)

Return the result of evaluating an expression against the source rows.

Value(Expr)

Return a fixed value, independent of the statement source.

Implementations

impl Returning

pub fn from_expr_iter<T>(items: impl IntoIterator<Item = T>) -> Returning

where T: Into<Expr>,

Creates a Returning::Expr from an iterator of expressions, combining them into a record expression.

pub fn is_model(&self) -> bool

Returns true if this is the Model variant.

pub fn model_includes(&self) -> &[Path]

Returns the association include paths for a Model variant, or an empty slice for other variants.

pub fn model_includes_mut_unwrap(&mut self) -> &mut Vec<Path>

Returns a mutable reference to the Model variant’s include paths.

Panics

Panics if this is not the Model variant.

pub fn is_changed(&self) -> bool

Returns true if this is the Changed variant.

pub fn is_expr(&self) -> bool

Returns true if this is the Expr variant.

pub fn as_expr(&self) -> Option<&Expr>

Returns a reference to the inner expression if this is the Expr variant.

pub fn as_expr_unwrap(&self) -> &Expr

Returns a reference to the inner expression.

Panics

Panics if this is not the Expr variant.

pub fn as_expr_mut(&mut self) -> Option<&mut Expr>

Returns a mutable reference to the inner expression if this is the Expr variant.

pub fn as_expr_mut_unwrap(&mut self) -> &mut Expr

Returns a mutable reference to the inner expression.

Panics

Panics if this is not the Expr variant.

pub fn set_expr(&mut self, expr: impl Into<Expr>)

Replaces this returning clause with Returning::Expr containing the given expression.

pub fn is_value(&self) -> bool

Returns true if this is the Value variant.

pub fn take(&mut self) -> Returning

Takes this returning clause, replacing it with Returning::Expr(null), and returns the original value.

Trait Implementations

impl Clone for Returning

fn clone(&self) -> Returning

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Returning

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

Formats the value using the given formatter.

impl From<Expr> for Returning

fn from(value: Expr) -> Returning

Converts to this type from the input type.

impl<T> From<T> for Returning

where Value: From<T>,

fn from(value: T) -> Returning

Converts to this type from the input type.

impl From<Vec<Expr>> for Returning

fn from(value: Vec<Expr>) -> Returning

Converts to this type from the input type.

impl Node for Returning

fn visit<V>(&self, visit: V)

where V: Visit, Returning: Sized,

Traverses this node with an immutable visitor.

fn visit_mut<V>(&mut self, visit: V)

where V: VisitMut,

Traverses this node with a mutable visitor.

impl PartialEq for Returning

fn eq(&self, other: &Returning) -> 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 Returning