1use crate::{2 create_error, future_wrapper, map::LayeredHashMap, rc_fn_helper, resolved_lazy_val, Error,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}21pub struct Context(Rc<ContextInternals>);22impl Debug for Context {23 fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {24 f.debug_struct("Context")25 .field("this", &self.0.this.as_ref().map(|e| Rc::as_ptr(&e.0)))26 .field("bindings", &self.0.bindings)27 .finish()28 }29}30impl Context {31 pub fn new_future() -> FutureContext {32 FutureContext(Rc::new(RefCell::new(None)))33 }3435 pub fn dollar(&self) -> &Option<ObjValue> {36 &self.0.dollar37 }3839 pub fn this(&self) -> &Option<ObjValue> {40 &self.0.this41 }4243 pub fn super_obj(&self) -> &Option<ObjValue> {44 &self.0.super_obj45 }4647 pub fn new() -> Context {48 Context(Rc::new(ContextInternals {49 dollar: None,50 this: None,51 super_obj: None,52 bindings: LayeredHashMap::default(),53 }))54 }5556 pub fn binding(&self, name: Rc<str>) -> Result<LazyVal> {57 self.0.bindings.get(&name).cloned().ok_or_else(|| {58 create_error::<()>(Error::UnknownVariable(name))59 .err()60 .unwrap()61 })62 }63 pub fn into_future(self, ctx: FutureContext) -> Context {64 {65 ctx.0.borrow_mut().replace(self);66 }67 ctx.unwrap()68 }6970 pub fn with_var(&self, name: Rc<str>, value: Val) -> Result<Context> {71 let mut new_bindings = HashMap::with_capacity(1);72 new_bindings.insert(name, resolved_lazy_val!(value));73 self.extend(new_bindings, None, None, None)74 }7576 pub fn extend(77 &self,78 new_bindings: HashMap<Rc<str>, LazyVal>,79 new_dollar: Option<ObjValue>,80 new_this: Option<ObjValue>,81 new_super_obj: Option<ObjValue>,82 ) -> Result<Context> {83 let dollar = new_dollar.or_else(|| self.0.dollar.clone());84 let this = new_this.or_else(|| self.0.this.clone());85 let super_obj = new_super_obj.or_else(|| self.0.super_obj.clone());86 let bindings = if new_bindings.is_empty() {87 self.0.bindings.clone()88 } else {89 self.0.bindings.extend(new_bindings)90 };91 Ok(Context(Rc::new(ContextInternals {92 dollar,93 this,94 super_obj,95 bindings,96 })))97 }98 pub fn extend_unbound(99 &self,100 new_bindings: HashMap<Rc<str>, LazyBinding>,101 new_dollar: Option<ObjValue>,102 new_this: Option<ObjValue>,103 new_super_obj: Option<ObjValue>,104 ) -> Result<Context> {105 let this = new_this.or_else(|| self.0.this.clone());106 let super_obj = new_super_obj.or_else(|| self.0.super_obj.clone());107 let mut new = HashMap::with_capacity(new_bindings.len());108 for (k, v) in new_bindings.into_iter() {109 new.insert(k, v.evaluate(this.clone(), super_obj.clone())?);110 }111 self.extend(new, new_dollar, this, super_obj)112 }113}114115impl Default for Context {116 fn default() -> Self {117 Self::new()118 }119}120121impl PartialEq for Context {122 fn eq(&self, other: &Self) -> bool {123 Rc::ptr_eq(&self.0, &other.0)124 }125}126127impl Clone for Context {128 fn clone(&self) -> Self {129 Context(self.0.clone())130 }131}