Enum Declaration 

pub enum Declaration<X: Extension = NoExt> {
    Variable {
        names: ThinVec<Ident>,
        data_type: DataType<X>,
        default: Option<Expr<X>>,
        meta: Meta,
    },
    Condition {
        name: Ident,
        value: ConditionValue,
        meta: Meta,
    },
    Cursor {
        name: Ident,
        query: Box<Query<X>>,
        meta: Meta,
    },
    Handler {
        action: HandlerAction,
        conditions: ThinVec<HandlerCondition>,
        body: Box<Statement<X>>,
        meta: Meta,
    },
}

One DECLARE … item in a CompoundStatement prefix.

The four forms are parsed uniformly into this prefix; their ordering is enforced post-hoc by the parser’s declaration 4-counter ({Variable, Condition} → Cursor → Handler), mirroring the server’s own mechanism rather than encoding the order as grammar productions.

Variants

Variable

DECLARE <name> [, <name> …] <type> [DEFAULT <expr>] — one or more local variables sharing a type and optional default.

Fields

names: ThinVec<Ident>

The declared variable names, in source order (always at least one).

data_type: DataType<X>

The shared declared type.

default: Option<Expr<X>>

The optional DEFAULT <expr> initializer.

meta: Meta

Source location and node identity.

Condition

DECLARE <name> CONDITION FOR <condition-value> — a named condition alias.

Fields

name: Ident

The condition name.

value: ConditionValue

The SQLSTATE '…' or MySQL error-code value the name aliases.

meta: Meta

Source location and node identity.

Cursor

DECLARE <name> CURSOR FOR <select> — a cursor over a query.

Fields

name: Ident

The cursor name.

query: Box<Query<X>>

The SELECT the cursor iterates; boxed to keep the variant small.

meta: Meta

Source location and node identity.

Handler

DECLARE {CONTINUE | EXIT | UNDO} HANDLER FOR <condition> [, …] <statement> — a condition handler whose body runs when any listed condition is raised.

Fields

action: HandlerAction

The handler action (CONTINUE/EXIT/UNDO).

conditions: ThinVec<HandlerCondition>

The condition values the handler catches, in source order (at least one).

body: Box<Statement<X>>

The handler body — a single body statement (often a compound block); boxed to keep the variant small.

meta: Meta

Source location and node identity.

Trait Implementations

impl<X: Clone + Extension> Clone for Declaration<X>

fn clone(&self) -> Declaration<X>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<X: Debug + Extension> Debug for Declaration<X>

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

Formats the value using the given formatter.

impl<'de, X> Deserialize<'de> for Declaration<X>

where X: Deserialize<'de> + Extension,

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<X: Eq + Extension> Eq for Declaration<X>

impl<X: Hash + Extension> Hash for Declaration<X>

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<X: PartialEq + Extension> PartialEq for Declaration<X>

fn eq(&self, other: &Declaration<X>) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl<X: Extension + Render> Render for Declaration<X>

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

Return the render for this value.

fn operand_binding_power(&self) -> Option<BindingPower>

The binding power this node contributes when it appears as an operand, or None (the default) for a self-delimiting node — an atom, call, or constructor — that never needs parentheses.

impl<X> Serialize for Declaration<X>

where X: Serialize + Extension,

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl<X: Extension> Spanned for Declaration<X>

fn span(&self) -> Span

Return the span for this value.

impl<X: PartialEq + Extension> StructuralPartialEq for Declaration<X>