Struct InsertSelectSource 

pub struct InsertSelectSource<S: Model, V> { /* private fields */ }

Source-tagged expression operand for FieldRef::copy_from / crate::query::DjogiField::copy_from.

What

InsertSelectSource<S, V> wraps the source-side projection IR for one position in an INSERT INTO ... SELECT ... mapping. The phantom S pins the operand to a specific source model so the mapping cannot silently cross model boundaries; the phantom V pins the value type so a target column of type V can only be fed by a source operand of the matching V.

How to construct

• From a source field — call FieldRef::as_insert_source / crate::query::DjogiField::as_insert_source. The receiver’s M pins the wrapper’s S, so building an operand from a target field gives an operand tagged with the target model which the closure return type then rejects.
• From a Rust scalar — call InsertSelectSource::literal. S is free at construction and inferred from the closure context (a constant has no source identity of its own).
• From an arithmetic composition — use + / - / * / / on InsertSelectSource<S, V> where V: Numeric. Same-S operands compose; mixing two different source tags fails to compile.

Why phantom-only

The IR payload (the crate-private ExprNode enum) is type-erased at the leaf — the SQL emitter walks one monomorphic function regardless of S or V. S and V are present strictly to drive compile-time checks at the mapping site; they never appear in the rendered SQL or in the SqlAccumulator’s bind list. Cf. the parallel design on crate::expr::Expr<V> — same rationale. Debug + Clone are derived because the inner IR tree is both. Copy is intentionally NOT implemented — the IR contains boxed sub-nodes, so cheap-looking Copy would hide allocation costs in arithmetic chains.

Implementations

impl<S: Model, V> InsertSelectSource<S, V>

pub fn literal(v: V) -> Self

where V: Into<Expr<V>>,

Build a literal source operand from a Rust scalar. The S parameter is polymorphic and inferred from the closure context — a literal has no source identity of its own, so any S satisfies the construction site. The closure’s return-type inference then pins S to the source model the enclosing QuerySet<S>::insert_into call uses.

Example

// Every archived row gets the same constant `status = "ARCHIVED"`.
.insert_into::<OrderArchive, _, _>(|target, _source| vec![
    target.status().copy_from(InsertSelectSource::literal("ARCHIVED".to_string())),
])

V: Into<Expr<V>> is satisfied by every scalar Djogi binds today (the crate-private crate::expr::literal module is the source of truth for the bindable set); the Into conversion routes through the same typed seal that Expr::literal uses.

Trait Implementations

impl<S: Model, V: Numeric> Add for InsertSelectSource<S, V>

type Output = InsertSelectSource<S, V>

The resulting type after applying the + operator.

fn add(self, rhs: Self) -> Self::Output

Performs the + operation.

impl<S: Model> Add<InsertSelectSource<S, Duration>> for InsertSelectSource<S, OffsetDateTime>

type Output = InsertSelectSource<S, OffsetDateTime>

The resulting type after applying the + operator.

fn add(self, rhs: InsertSelectSource<S, Duration>) -> Self::Output

Performs the + operation.

impl<S: Clone + Model, V: Clone> Clone for InsertSelectSource<S, V>

fn clone(&self) -> InsertSelectSource<S, V>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<S: Debug + Model, V: Debug> Debug for InsertSelectSource<S, V>

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

Formats the value using the given formatter.

impl<S: Model, V: Numeric> Div for InsertSelectSource<S, V>

type Output = InsertSelectSource<S, V>

The resulting type after applying the / operator.

fn div(self, rhs: Self) -> Self::Output

Performs the / operation.

impl<S: Model, V: Numeric> Mul for InsertSelectSource<S, V>

type Output = InsertSelectSource<S, V>

The resulting type after applying the * operator.

fn mul(self, rhs: Self) -> Self::Output

Performs the * operation.

impl<S: Model, V: Numeric> Sub for InsertSelectSource<S, V>

type Output = InsertSelectSource<S, V>

The resulting type after applying the - operator.

fn sub(self, rhs: Self) -> Self::Output

Performs the - operation.

impl<S: Model> Sub<InsertSelectSource<S, Duration>> for InsertSelectSource<S, OffsetDateTime>

type Output = InsertSelectSource<S, OffsetDateTime>

The resulting type after applying the - operator.

fn sub(self, rhs: InsertSelectSource<S, Duration>) -> Self::Output

Performs the - operation.