git.delta.rocks / jrsonnet / refs/commits / ff3e2c836938

1use std::borrow::Cow;23use jrsonnet_gcmodule::Trace;45use super::{arglike::ArgsLike, parse::parse_builtin_call, CallLocation};6use crate::{error::Result, gc::TraceBox, Context, State, Val};78pub type BuiltinParamName = Cow<'static, str>;910#[derive(Clone, Trace)]11pub struct BuiltinParam {12	/// Parameter name for named call parsing13	pub name: Option<BuiltinParamName>,14	/// Is implementation allowed to return empty value15	pub has_default: bool,16}1718/// Description of function defined by native code19///20/// Prefer to use #[builtin] macro, instead of manual implementation of this trait21pub trait Builtin: Trace {22	/// Function name to be used in stack traces23	fn name(&self) -> &str;24	/// Parameter names for named calls25	fn params(&self) -> &[BuiltinParam];26	/// Call the builtin27	fn call(28		&self,29		s: State,30		ctx: Context,31		loc: CallLocation<'_>,32		args: &dyn ArgsLike,33	) -> Result<Val>;34}3536pub trait StaticBuiltin: Builtin + Send + Sync37where38	Self: 'static,39{40	// In impl, to make it object safe:41	// const INST: &'static Self;42}4344#[derive(Trace)]45pub struct NativeCallback {46	pub(crate) params: Vec<BuiltinParam>,47	handler: TraceBox<dyn NativeCallbackHandler>,48}49impl NativeCallback {50	#[deprecated = "prefer using builtins directly, use this interface only for bindings"]51	pub fn new(52		params: Vec<Cow<'static, str>>,53		handler: TraceBox<dyn NativeCallbackHandler>,54	) -> Self {55		Self {56			params: params57				.into_iter()58				.map(|n| BuiltinParam {59					name: Some(n),60					has_default: false,61				})62				.collect(),63			handler,64		}65	}66}6768impl Builtin for NativeCallback {69	fn name(&self) -> &str {70		// TODO: standard natives gets their names from definition71		// But builitins should already have them72		"<native>"73	}7475	fn params(&self) -> &[BuiltinParam] {76		&self.params77	}7879	fn call(80		&self,81		s: State,82		ctx: Context,83		_loc: CallLocation<'_>,84		args: &dyn ArgsLike,85	) -> Result<Val> {86		let args = parse_builtin_call(s.clone(), ctx, &self.params, args, true)?;87		let args = args88			.into_iter()89			.map(|a| a.expect("legacy natives have no default params"))90			.map(|a| a.evaluate(s.clone()))91			.collect::<Result<Vec<Val>>>()?;92		self.handler.call(s, &args)93	}94}9596pub trait NativeCallbackHandler: Trace {97	fn call(&self, s: State, args: &[Val]) -> Result<Val>;98}