Enum rtlola_frontend::ast::ExpressionKind

pub enum ExpressionKind {
    Lit(Literal),
    Ident(Ident),
    StreamAccess(Box<Expression>, StreamAccessKind),
    Default(Box<Expression>, Box<Expression>),
    Offset(Box<Expression>, Offset),
    DiscreteWindowAggregation {
        expr: Box<Expression>,
        duration: Box<Expression>,
        wait: bool,
        aggregation: WindowOperation,
    },
    SlidingWindowAggregation {
        expr: Box<Expression>,
        duration: Box<Expression>,
        wait: bool,
        aggregation: WindowOperation,
    },
    Binary(BinOp, Box<Expression>, Box<Expression>),
    Unary(UnOp, Box<Expression>),
    Ite(Box<Expression>, Box<Expression>, Box<Expression>),
    ParenthesizedExpression(Option<Box<Parenthesis>>, Box<Expression>, Option<Box<Parenthesis>>),
    MissingExpression,
    Tuple(Vec<Box<Expression>>),
    Field(Box<Expression>, Ident),
    Method(Box<Expression>, FunctionName, Vec<Type>, Vec<Box<Expression>>),
    Function(FunctionName, Vec<Type>, Vec<Box<Expression>>),
}

The AST representation of a single expression

Variants

Lit(Literal)

A literal, e.g., 1, "foo"

Ident(Ident)

An identifier, e.g., foo

StreamAccess(Box<Expression>, StreamAccessKind)

Accessing a stream

Default(Box<Expression>, Box<Expression>)

A default expression, e.g., a.defaults(to: 0)

Offset(Box<Expression>, Offset)

An offset expression, e.g., a.offset(by: -1)

DiscreteWindowAggregation

A discrete window with a duration duration as an integer constant and aggregation function aggregation

Fields of DiscreteWindowAggregation

expr: Box<Expression>

The accesses stream

duration: Box<Expression>

The duration of the window

wait: bool

Flag to mark that the window returns only a value if the complete duration has passed

aggregation: WindowOperation

The aggregation function

SlidingWindowAggregation

A sliding window with duration duration and aggregation function aggregation

Fields of SlidingWindowAggregation

expr: Box<Expression>

The accesses stream

duration: Box<Expression>

The duration of the window

wait: bool

Flag to mark that the window returns only a value if the complete duration has passed

aggregation: WindowOperation

The aggregation function

Binary(BinOp, Box<Expression>, Box<Expression>)

A binary operation (For example: a + b, a * b)

Unary(UnOp, Box<Expression>)

A unary operation (For example: !x, *x)

Ite(Box<Expression>, Box<Expression>, Box<Expression>)

An if-then-else expression

ParenthesizedExpression(Option<Box<Parenthesis>>, Box<Expression>, Option<Box<Parenthesis>>)

An expression enveloped in parentheses

MissingExpression

An expression was expected, e.g., after an operator like *

Tuple(Vec<Box<Expression>>)

A tuple expression

Field(Box<Expression>, Ident)

Access of a named (obj.foo) or unnamed (obj.0) struct field

Method(Box<Expression>, FunctionName, Vec<Type>, Vec<Box<Expression>>)

A method call, e.g., foo.bar(-1)

Function(FunctionName, Vec<Type>, Vec<Box<Expression>>)

A function call

Trait Implementations

impl Clone for ExpressionKind

pub fn clone(&self) -> ExpressionKind

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ExpressionKind

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

Formats the value using the given formatter.