Struct FunctionAttr

pub(crate) struct FunctionAttr {

    pub(crate) name: String,
    pub(crate) args: Vec<String>,
    pub(crate) ret: String,
    pub(crate) is_table_function: bool,
    pub(crate) append_only: bool,
    pub(crate) batch_fn: Option<String>,
    pub(crate) state: Option<String>,
    pub(crate) init_state: Option<String>,
    pub(crate) prebuild: Option<String>,
    pub(crate) type_infer: Option<String>,
    pub(crate) generic: Option<String>,
    pub(crate) volatile: bool,
    pub(crate) deprecated: bool,
    pub(crate) rewritten: bool,
}

Fields

name: String

Function name

args: Vec<String>

Input argument types

ret: String

Return type

is_table_function: bool

Whether it is a table function

append_only: bool

Whether it is an append-only aggregate function

batch_fn: Option<String>

Optional function for batch evaluation.

state: Option<String>

State type for aggregate function. If not specified, it will be the same as return type.

init_state: Option<String>

Initial state value for aggregate function. If not specified, it will be NULL.

prebuild: Option<String>

Prebuild function for arguments. This could be any Rust expression.

type_infer: Option<String>

Type inference function.

generic: Option<String>

Generic type.

volatile: bool

Whether the function is volatile.

deprecated: bool

If true, the function is unavailable on the frontend.

rewritten: bool

If true, the function is not implemented on the backend, but its signature is defined.

Implementations

impl FunctionAttr

pub fn expand(&self) -> Vec<Self>

Expands the wildcard in function arguments or return type.

fn generate_type_infer_fn(&self) -> Result<TokenStream2>

Generate the type infer function: fn(&[DataType]) -> Result<DataType>

pub fn generate_function_descriptor( &self, user_fn: &UserFunctionAttr, build_fn: bool, ) -> Result<TokenStream2>

Generate a descriptor (FuncSign) of the scalar or table function.

The types of arguments and return value should not contain wildcard.

Arguments

build_fn: whether the user provided a function is a build function. (from the #[build_function] macro)

fn generate_build_scalar_function( &self, user_fn: &UserFunctionAttr, optimize_const: bool, ) -> Result<TokenStream2>

Generate a build function for the scalar function.

If optimize_const is true, the function will be optimized for constant arguments, and fallback to the general version if any argument is not constant.

pub fn generate_aggregate_descriptor( &self, user_fn: &AggregateFnOrImpl, build_fn: bool, ) -> Result<TokenStream2>

Generate a descriptor of the aggregate function.

The types of arguments and return value should not contain wildcard. user_fn could be either fn or impl. If build_fn is true, user_fn must be a fn that builds the aggregate function.

fn generate_agg_build_fn( &self, user_fn: &AggregateFnOrImpl, ) -> Result<TokenStream2>

Generate build function for aggregate function.

fn generate_table_function_descriptor( &self, user_fn: &UserFunctionAttr, build_fn: bool, ) -> Result<TokenStream2>

Generate a descriptor of the table function.

The types of arguments and return value should not contain wildcard.

fn generate_build_table_function( &self, user_fn: &UserFunctionAttr, ) -> Result<TokenStream2>

impl FunctionAttr

pub(crate) fn ident_name(&self) -> String

Return a unique name that can be used as an identifier.

Trait Implementations

impl Clone for FunctionAttr

fn clone(&self) -> FunctionAttr

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for FunctionAttr

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

Formats the value using the given formatter.

impl Default for FunctionAttr

fn default() -> FunctionAttr

Returns the “default value” for a type.

impl Parse for FunctionAttr

fn parse(input: ParseStream<'_>) -> Result<Self>

Parse the attribute of the function macro.