git.delta.rocks / jrsonnet / refs/commits / 1d4b842070e4

1use crate::{2	error::Error::*, future_wrapper, map::LayeredHashMap, rc_fn_helper, resolved_lazy_val,3	LazyBinding, LazyVal, ObjValue, Result, Val,4};5use std::{cell::RefCell, collections::HashMap, fmt::Debug, rc::Rc};67rc_fn_helper!(8	ContextCreator,9	context_creator,10	dyn Fn(Option<ObjValue>, Option<ObjValue>) -> Result<Context>11);1213future_wrapper!(Context, FutureContext);1415struct ContextInternals {16	dollar: Option<ObjValue>,17	this: Option<ObjValue>,18	super_obj: Option<ObjValue>,19	bindings: LayeredHashMap<Rc<str>, LazyVal>,20}21impl Debug for ContextInternals {22	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {23		f.debug_struct("Context")24			.field("this", &self.this.as_ref().map(|e| Rc::as_ptr(&e.0)))25			.field("bindings", &self.bindings)26			.finish()27	}28}2930#[derive(Debug, Clone)]31pub struct Context(Rc<ContextInternals>);32impl Context {33	pub fn new_future() -> FutureContext {34		FutureContext(Rc::new(RefCell::new(None)))35	}3637	pub fn dollar(&self) -> &Option<ObjValue> {38		&self.0.dollar39	}4041	pub fn this(&self) -> &Option<ObjValue> {42		&self.0.this43	}4445	pub fn super_obj(&self) -> &Option<ObjValue> {46		&self.0.super_obj47	}4849	pub fn new() -> Context {50		Context(Rc::new(ContextInternals {51			dollar: None,52			this: None,53			super_obj: None,54			bindings: LayeredHashMap::default(),55		}))56	}5758	pub fn binding(&self, name: Rc<str>) -> Result<LazyVal> {59		Ok(self60			.061			.bindings62			.get(&name)63			.cloned()64			.ok_or_else(|| UnknownVariable(name))?)65	}66	pub fn into_future(self, ctx: FutureContext) -> Context {67		{68			ctx.0.borrow_mut().replace(self);69		}70		ctx.unwrap()71	}7273	pub fn with_var(self, name: Rc<str>, value: Val) -> Context {74		let mut new_bindings = HashMap::with_capacity(1);75		new_bindings.insert(name, resolved_lazy_val!(value));76		self.extend(new_bindings, None, None, None)77	}7879	pub fn extend(80		self,81		new_bindings: HashMap<Rc<str>, LazyVal>,82		new_dollar: Option<ObjValue>,83		new_this: Option<ObjValue>,84		new_super_obj: Option<ObjValue>,85	) -> Context {86		match Rc::try_unwrap(self.0) {87			Ok(mut ctx) => {88				// Extended context aren't used by anything else, we can freely mutate it without cloning89				if let Some(dollar) = new_dollar {90					ctx.dollar = Some(dollar);91				}92				if let Some(this) = new_this {93					ctx.this = Some(this);94				}95				if let Some(super_obj) = new_super_obj {96					ctx.super_obj = Some(super_obj);97				}98				if !new_bindings.is_empty() {99					ctx.bindings = ctx.bindings.extend(new_bindings);100				}101				Context(Rc::new(ctx))102			}103			Err(ctx) => {104				let dollar = new_dollar.or_else(|| ctx.dollar.clone());105				let this = new_this.or_else(|| ctx.this.clone());106				let super_obj = new_super_obj.or_else(|| ctx.super_obj.clone());107				let bindings = if new_bindings.is_empty() {108					ctx.bindings.clone()109				} else {110					ctx.bindings.clone().extend(new_bindings)111				};112				Context(Rc::new(ContextInternals {113					dollar,114					this,115					super_obj,116					bindings,117				}))118			}119		}120	}121	pub fn extend_unbound(122		self,123		new_bindings: HashMap<Rc<str>, LazyBinding>,124		new_dollar: Option<ObjValue>,125		new_this: Option<ObjValue>,126		new_super_obj: Option<ObjValue>,127	) -> Result<Context> {128		let this = new_this.or_else(|| self.0.this.clone());129		let super_obj = new_super_obj.or_else(|| self.0.super_obj.clone());130		let mut new = HashMap::with_capacity(new_bindings.len());131		for (k, v) in new_bindings.into_iter() {132			new.insert(k, v.evaluate(this.clone(), super_obj.clone())?);133		}134		Ok(self.extend(new, new_dollar, this, super_obj))135	}136	#[cfg(feature = "unstable")]137	pub fn into_weak(self) -> WeakContext {138		WeakContext(Rc::downgrade(&self.0))139	}140}141142impl Default for Context {143	fn default() -> Self {144		Self::new()145	}146}147148impl PartialEq for Context {149	fn eq(&self, other: &Self) -> bool {150		Rc::ptr_eq(&self.0, &other.0)151	}152}153154#[cfg(feature = "unstable")]155#[derive(Debug, Clone)]156pub struct WeakContext(std::rc::Weak<ContextInternals>);157#[cfg(feature = "unstable")]158impl WeakContext {159	pub fn upgrade(&self) -> Context {160		Context(self.0.upgrade().expect("context is removed"))161	}162}163#[cfg(feature = "unstable")]164impl PartialEq for WeakContext {165	fn eq(&self, other: &Self) -> bool {166		self.0.ptr_eq(&other.0)167	}168}