rhai/src/eval/chaining.rs
2023-04-05 23:40:27 +08:00

1006 lines
43 KiB
Rust

//! Types to support chaining operations (i.e. indexing and dotting).
#![cfg(any(not(feature = "no_index"), not(feature = "no_object")))]
use super::{Caches, GlobalRuntimeState, Target};
use crate::ast::{ASTFlags, BinaryExpr, Expr, OpAssignment};
use crate::config::hashing::SusLock;
use crate::engine::{FN_IDX_GET, FN_IDX_SET};
use crate::types::dynamic::Union;
use crate::{
calc_fn_hash, Dynamic, Engine, FnArgsVec, Position, RhaiResult, RhaiResultOf, Scope, ERR,
};
use std::hash::Hash;
#[cfg(feature = "no_std")]
use std::prelude::v1::*;
/// Function call hashes to index getters and setters.
///
/// # Safety
///
/// Uses the extremely unsafe [`SusLock`]. Change to [`OnceCell`] when it is stabilized.
static INDEXER_HASHES: SusLock<(u64, u64)> = SusLock::new();
/// Get the pre-calculated index getter/setter hashes.
#[inline(always)]
#[must_use]
fn hash_idx() -> (u64, u64) {
*INDEXER_HASHES.get_or_init(|| {
(
calc_fn_hash(None, FN_IDX_GET, 2),
calc_fn_hash(None, FN_IDX_SET, 3),
)
})
}
/// Method of chaining.
#[derive(Debug, Clone, Copy, Eq, PartialEq, Hash)]
pub enum ChainType {
/// Indexing.
#[cfg(not(feature = "no_index"))]
Indexing,
/// Dotting.
#[cfg(not(feature = "no_object"))]
Dotting,
}
impl From<&Expr> for ChainType {
#[inline(always)]
fn from(expr: &Expr) -> Self {
match expr {
#[cfg(not(feature = "no_index"))]
Expr::Index(..) => Self::Indexing,
#[cfg(not(feature = "no_object"))]
Expr::Dot(..) => Self::Dotting,
expr => unreachable!("Expr::Index or Expr::Dot expected but gets {:?}", expr),
}
}
}
impl Engine {
/// Call a get indexer.
#[inline]
fn call_indexer_get(
&self,
global: &mut GlobalRuntimeState,
caches: &mut Caches,
target: &mut Dynamic,
idx: &mut Dynamic,
pos: Position,
) -> RhaiResultOf<Dynamic> {
defer! { let orig_level = global.level; global.level += 1 }
let hash = hash_idx().0;
let args = &mut [target, idx];
self.exec_native_fn_call(global, caches, FN_IDX_GET, None, hash, args, true, pos)
.map(|(r, ..)| r)
}
/// Call a set indexer.
#[inline]
fn call_indexer_set(
&self,
global: &mut GlobalRuntimeState,
caches: &mut Caches,
target: &mut Dynamic,
idx: &mut Dynamic,
new_val: &mut Dynamic,
is_ref_mut: bool,
pos: Position,
) -> RhaiResultOf<(Dynamic, bool)> {
defer! { let orig_level = global.level; global.level += 1 }
let hash = hash_idx().1;
let args = &mut [target, idx, new_val];
self.exec_native_fn_call(
global, caches, FN_IDX_SET, None, hash, args, is_ref_mut, pos,
)
}
/// Get the value at the indexed position of a base type.
fn get_indexed_mut<'t>(
&self,
global: &mut GlobalRuntimeState,
caches: &mut Caches,
target: &'t mut Dynamic,
idx: &mut Dynamic,
idx_pos: Position,
op_pos: Position,
_add_if_not_found: bool,
use_indexers: bool,
) -> RhaiResultOf<Target<'t>> {
self.track_operation(global, Position::NONE)?;
match target {
#[cfg(not(feature = "no_index"))]
Dynamic(Union::Array(arr, ..)) => {
// val_array[idx]
let index = idx
.as_int()
.map_err(|typ| self.make_type_mismatch_err::<crate::INT>(typ, idx_pos))?;
let len = arr.len();
let arr_idx = super::calc_index(len, index, true, || {
ERR::ErrorArrayBounds(len, index, idx_pos).into()
})?;
Ok(arr.get_mut(arr_idx).map(Target::from).unwrap())
}
#[cfg(not(feature = "no_index"))]
Dynamic(Union::Blob(arr, ..)) => {
// val_blob[idx]
let index = idx
.as_int()
.map_err(|typ| self.make_type_mismatch_err::<crate::INT>(typ, idx_pos))?;
let len = arr.len();
let arr_idx = super::calc_index(len, index, true, || {
ERR::ErrorArrayBounds(len, index, idx_pos).into()
})?;
let value = arr.get(arr_idx).map(|&v| (v as crate::INT).into()).unwrap();
Ok(Target::BlobByte {
source: target,
value,
index: arr_idx,
})
}
#[cfg(not(feature = "no_object"))]
Dynamic(Union::Map(map, ..)) => {
// val_map[idx]
let index = idx.read_lock::<crate::ImmutableString>().ok_or_else(|| {
self.make_type_mismatch_err::<crate::ImmutableString>(idx.type_name(), idx_pos)
})?;
if _add_if_not_found && (map.is_empty() || !map.contains_key(index.as_str())) {
map.insert(index.clone().into(), Dynamic::UNIT);
}
map.get_mut(index.as_str()).map_or_else(
|| {
if self.fail_on_invalid_map_property() {
Err(ERR::ErrorPropertyNotFound(index.to_string(), idx_pos).into())
} else {
Ok(Target::from(Dynamic::UNIT))
}
},
|value| Ok(Target::from(value)),
)
}
#[cfg(not(feature = "no_index"))]
Dynamic(Union::Int(value, ..))
if idx.is::<crate::ExclusiveRange>() || idx.is::<crate::InclusiveRange>() =>
{
// val_int[range]
let (shift, mask) = if let Some(range) = idx.read_lock::<crate::ExclusiveRange>() {
let start = range.start;
let end = range.end;
let start = super::calc_index(crate::INT_BITS, start, false, || {
ERR::ErrorBitFieldBounds(crate::INT_BITS, start, idx_pos).into()
})?;
let end = super::calc_index(crate::INT_BITS, end, false, || {
ERR::ErrorBitFieldBounds(crate::INT_BITS, end, idx_pos).into()
})?;
#[allow(clippy::cast_possible_truncation)]
if end <= start {
(0, 0)
} else if end == crate::INT_BITS && start == 0 {
// -1 = all bits set
(0, -1)
} else {
(
start as u8,
// 2^bits - 1
(((2 as crate::UNSIGNED_INT).pow((end - start) as u32) - 1)
as crate::INT)
<< start,
)
}
} else if let Some(range) = idx.read_lock::<crate::InclusiveRange>() {
let start = *range.start();
let end = *range.end();
let start = super::calc_index(crate::INT_BITS, start, false, || {
ERR::ErrorBitFieldBounds(crate::INT_BITS, start, idx_pos).into()
})?;
let end = super::calc_index(crate::INT_BITS, end, false, || {
ERR::ErrorBitFieldBounds(crate::INT_BITS, end, idx_pos).into()
})?;
#[allow(clippy::cast_possible_truncation)]
if end < start {
(0, 0)
} else if end == crate::INT_BITS - 1 && start == 0 {
// -1 = all bits set
(0, -1)
} else {
(
start as u8,
// 2^bits - 1
(((2 as crate::UNSIGNED_INT).pow((end - start + 1) as u32) - 1)
as crate::INT)
<< start,
)
}
} else {
unreachable!("Range or RangeInclusive expected but gets {:?}", idx);
};
let field_value = (*value & mask) >> shift;
Ok(Target::BitField {
source: target,
value: field_value.into(),
mask,
shift,
})
}
#[cfg(not(feature = "no_index"))]
Dynamic(Union::Int(value, ..)) => {
// val_int[idx]
let index = idx
.as_int()
.map_err(|typ| self.make_type_mismatch_err::<crate::INT>(typ, idx_pos))?;
let bit = super::calc_index(crate::INT_BITS, index, true, || {
ERR::ErrorBitFieldBounds(crate::INT_BITS, index, idx_pos).into()
})?;
let bit_value = (*value & (1 << bit)) != 0;
#[allow(clippy::cast_possible_truncation)]
let bit = bit as u8;
Ok(Target::Bit {
source: target,
value: bit_value.into(),
bit,
})
}
#[cfg(not(feature = "no_index"))]
Dynamic(Union::Str(s, ..)) => {
// val_string[idx]
let index = idx
.as_int()
.map_err(|typ| self.make_type_mismatch_err::<crate::INT>(typ, idx_pos))?;
let (ch, offset) = if index >= 0 {
#[allow(clippy::absurd_extreme_comparisons)]
if index >= crate::MAX_USIZE_INT {
return Err(
ERR::ErrorStringBounds(s.chars().count(), index, idx_pos).into()
);
}
#[allow(clippy::cast_sign_loss, clippy::cast_possible_truncation)]
let offset = index as usize;
(
s.chars().nth(offset).ok_or_else(|| {
ERR::ErrorStringBounds(s.chars().count(), index, idx_pos)
})?,
offset,
)
} else {
let abs_index = index.unsigned_abs();
if abs_index as u64 > usize::MAX as u64 {
return Err(
ERR::ErrorStringBounds(s.chars().count(), index, idx_pos).into()
);
}
#[allow(clippy::cast_possible_truncation)]
let offset = abs_index as usize;
(
// Count from end if negative
s.chars().rev().nth(offset - 1).ok_or_else(|| {
ERR::ErrorStringBounds(s.chars().count(), index, idx_pos)
})?,
offset,
)
};
Ok(Target::StringChar {
source: target,
value: ch.into(),
index: offset,
})
}
#[cfg(not(feature = "no_closure"))]
Dynamic(Union::Shared(..)) => {
unreachable!("`get_indexed_mut` cannot handle shared values")
}
_ if use_indexers => self
.call_indexer_get(global, caches, target, idx, op_pos)
.map(Into::into),
_ => Err(ERR::ErrorIndexingType(
format!(
"{} [{}]",
self.map_type_name(target.type_name()),
self.map_type_name(idx.type_name())
),
op_pos,
)
.into()),
}
}
/// Evaluate a dot/index chain.
pub(crate) fn eval_dot_index_chain(
&self,
global: &mut GlobalRuntimeState,
caches: &mut Caches,
scope: &mut Scope,
mut this_ptr: Option<&mut Dynamic>,
expr: &Expr,
new_val: Option<(Dynamic, &OpAssignment)>,
) -> RhaiResult {
let BinaryExpr { lhs, rhs } = match expr {
#[cfg(not(feature = "no_index"))]
Expr::Index(x, ..) => &**x,
#[cfg(not(feature = "no_object"))]
Expr::Dot(x, ..) => &**x,
expr => unreachable!("Expr::Index or Expr::Dot expected but gets {:?}", expr),
};
let idx_values = &mut FnArgsVec::new_const();
match (rhs, ChainType::from(expr)) {
// Short-circuit for simple property access: {expr}.prop
#[cfg(not(feature = "no_object"))]
(Expr::Property(..), ChainType::Dotting) => (),
#[cfg(not(feature = "no_object"))]
(Expr::Property(..), ..) => {
unreachable!("unexpected Expr::Property for indexing")
}
// Short-circuit for indexing with literal: {expr}[1]
#[cfg(not(feature = "no_index"))]
(_, ChainType::Indexing) if rhs.is_constant() => {
idx_values.push(rhs.get_literal_value().unwrap())
}
// Short-circuit for simple method call: {expr}.func()
#[cfg(not(feature = "no_object"))]
(Expr::MethodCall(x, ..), ChainType::Dotting) if x.args.is_empty() => (),
// All other patterns - evaluate the arguments chain
_ => self.eval_dot_index_chain_arguments(
global,
caches,
scope,
this_ptr.as_deref_mut(),
expr,
rhs,
idx_values,
)?,
}
#[cfg(feature = "debugging")]
let scope2 = &mut Scope::new();
#[cfg(not(feature = "debugging"))]
let scope2 = ();
match (lhs, new_val) {
// id.??? or id[???]
(Expr::Variable(.., var_pos), new_val) => {
self.track_operation(global, *var_pos)?;
#[cfg(feature = "debugging")]
self.run_debugger(global, caches, scope, this_ptr.as_deref_mut(), lhs)?;
let target = &mut self.search_namespace(global, caches, scope, this_ptr, lhs)?;
self.eval_dot_index_chain_raw(
global, caches, scope2, None, lhs, expr, target, rhs, idx_values, new_val,
)
}
// {expr}.??? = ??? or {expr}[???] = ???
(_, Some(..)) => unreachable!("cannot assign to an expression"),
// {expr}.??? or {expr}[???]
(lhs_expr, None) => {
let value = self
.eval_expr(global, caches, scope, this_ptr.as_deref_mut(), lhs_expr)?
.flatten();
let obj_ptr = &mut value.into();
self.eval_dot_index_chain_raw(
global, caches, scope2, this_ptr, lhs_expr, expr, obj_ptr, rhs, idx_values,
None,
)
}
}
.map(|(v, ..)| v)
}
/// Evaluate a chain of indexes and store the results in a [`FnArgsVec`].
fn eval_dot_index_chain_arguments(
&self,
global: &mut GlobalRuntimeState,
caches: &mut Caches,
scope: &mut Scope,
mut this_ptr: Option<&mut Dynamic>,
parent: &Expr,
expr: &Expr,
idx_values: &mut FnArgsVec<Dynamic>,
) -> RhaiResultOf<()> {
self.track_operation(global, expr.position())?;
match (expr, ChainType::from(parent)) {
#[cfg(not(feature = "no_object"))]
(Expr::MethodCall(x, ..), ChainType::Dotting) => {
debug_assert!(
!x.is_qualified(),
"method call in dot chain should not be namespace-qualified"
);
for expr in &x.args {
let arg_value =
self.get_arg_value(global, caches, scope, this_ptr.as_deref_mut(), expr)?;
idx_values.push(arg_value.0.flatten());
}
}
#[cfg(not(feature = "no_object"))]
(Expr::Property(..), ChainType::Dotting) => (),
(Expr::Index(x, ..) | Expr::Dot(x, ..), chain_type)
if !parent.options().contains(ASTFlags::BREAK) =>
{
let BinaryExpr { lhs, rhs, .. } = &**x;
let mut _arg_values = FnArgsVec::new_const();
// Evaluate in left-to-right order
match (lhs, chain_type) {
#[cfg(not(feature = "no_object"))]
(Expr::Property(..), ChainType::Dotting) => (),
#[cfg(not(feature = "no_object"))]
(Expr::MethodCall(x, ..), ChainType::Dotting) => {
debug_assert!(
!x.is_qualified(),
"method call in dot chain should not be namespace-qualified"
);
for expr in &x.args {
let tp = this_ptr.as_deref_mut();
let arg_value = self.get_arg_value(global, caches, scope, tp, expr)?;
_arg_values.push(arg_value.0.flatten());
}
}
#[cfg(not(feature = "no_index"))]
(_, ChainType::Indexing) => {
_arg_values.push(
self.eval_expr(global, caches, scope, this_ptr.as_deref_mut(), lhs)?
.flatten(),
);
}
#[allow(unreachable_patterns)]
(expr, chain_type) => {
unreachable!("unknown {:?} expression: {:?}", chain_type, expr)
}
}
// Push in reverse order
self.eval_dot_index_chain_arguments(
global, caches, scope, this_ptr, expr, rhs, idx_values,
)?;
idx_values.extend(_arg_values);
}
#[cfg(not(feature = "no_index"))]
(_, ChainType::Indexing) => idx_values.push(
self.eval_expr(global, caches, scope, this_ptr, expr)?
.flatten(),
),
#[allow(unreachable_patterns)]
(expr, chain_type) => unreachable!("unknown {:?} expression: {:?}", chain_type, expr),
}
Ok(())
}
/// Chain-evaluate a dot/index chain.
fn eval_dot_index_chain_raw(
&self,
global: &mut GlobalRuntimeState,
caches: &mut Caches,
#[cfg(feature = "debugging")] scope: &mut Scope,
#[cfg(not(feature = "debugging"))] scope: (),
this_ptr: Option<&mut Dynamic>,
root: &Expr,
parent: &Expr,
target: &mut Target,
rhs: &Expr,
idx_values: &mut FnArgsVec<Dynamic>,
new_val: Option<(Dynamic, &OpAssignment)>,
) -> RhaiResultOf<(Dynamic, bool)> {
let is_ref_mut = target.is_ref();
let op_pos = parent.position();
#[cfg(feature = "debugging")]
#[allow(unused_mut)]
let mut this_ptr = this_ptr;
match ChainType::from(parent) {
#[cfg(not(feature = "no_index"))]
ChainType::Indexing => {
// Check for existence with the null conditional operator
if parent.options().contains(ASTFlags::NEGATED) && target.is_unit() {
return Ok((Dynamic::UNIT, false));
}
let pos = rhs.start_position();
match (rhs, new_val) {
// xxx[idx].expr... | xxx[idx][expr]...
(Expr::Dot(x, ..) | Expr::Index(x, ..), new_val)
if !parent.options().contains(ASTFlags::BREAK) =>
{
#[cfg(feature = "debugging")]
self.run_debugger(global, caches, scope, this_ptr.as_deref_mut(), parent)?;
let idx_val = &mut idx_values.pop().unwrap();
let mut idx_val_for_setter = idx_val.clone();
let idx_pos = x.lhs.start_position();
let (try_setter, result) = {
let mut obj = self.get_indexed_mut(
global, caches, target, idx_val, idx_pos, op_pos, false, true,
)?;
let is_obj_temp_val = obj.is_temp_value();
let obj_ptr = &mut obj;
match self.eval_dot_index_chain_raw(
global, caches, scope, this_ptr, root, rhs, obj_ptr, &x.rhs,
idx_values, new_val,
) {
Ok((result, true)) if is_obj_temp_val => {
(Some(obj.take_or_clone()), (result, true))
}
Ok(result) => (None, result),
Err(err) => return Err(err),
}
};
if let Some(mut new_val) = try_setter {
// Try to call index setter if value is changed
let idx = &mut idx_val_for_setter;
let new_val = &mut new_val;
// The return value of a indexer setter (usually `()`) is thrown away and not used.
let _ = self
.call_indexer_set(
global, caches, target, idx, new_val, is_ref_mut, op_pos,
)
.or_else(|e| match *e {
ERR::ErrorIndexingType(..) => Ok((Dynamic::UNIT, false)),
_ => Err(e),
})?;
}
Ok(result)
}
// xxx[rhs] op= new_val
(_, Some((new_val, op_info))) => {
#[cfg(feature = "debugging")]
self.run_debugger(global, caches, scope, this_ptr, parent)?;
let idx_val = &mut idx_values.pop().unwrap();
let idx = &mut idx_val.clone();
let try_setter = match self
.get_indexed_mut(global, caches, target, idx, pos, op_pos, true, false)
{
// Indexed value is not a temp value - update directly
Ok(ref mut obj_ptr) => {
self.eval_op_assignment(
global, caches, op_info, root, obj_ptr, new_val,
)?;
self.check_data_size(obj_ptr.as_ref(), op_info.position())?;
None
}
// Indexed value cannot be referenced - use indexer
#[cfg(not(feature = "no_index"))]
Err(err) if matches!(*err, ERR::ErrorIndexingType(..)) => Some(new_val),
// Any other error
Err(err) => return Err(err),
};
if let Some(mut new_val) = try_setter {
// Is this an op-assignment?
if op_info.is_op_assignment() {
let idx = &mut idx_val.clone();
// Call the index getter to get the current value
if let Ok(val) =
self.call_indexer_get(global, caches, target, idx, op_pos)
{
let mut val = val.into();
// Run the op-assignment
self.eval_op_assignment(
global, caches, op_info, root, &mut val, new_val,
)?;
// Replace new value
new_val = val.take_or_clone();
self.check_data_size(&new_val, op_info.position())?;
}
}
// Try to call index setter
let new_val = &mut new_val;
// The return value of a indexer setter (usually `()`) is thrown away and not used.
let _ = self.call_indexer_set(
global, caches, target, idx_val, new_val, is_ref_mut, op_pos,
)?;
}
Ok((Dynamic::UNIT, true))
}
// xxx[rhs]
(_, None) => {
#[cfg(feature = "debugging")]
self.run_debugger(global, caches, scope, this_ptr, parent)?;
let idx_val = &mut idx_values.pop().unwrap();
self.get_indexed_mut(
global, caches, target, idx_val, pos, op_pos, false, true,
)
.map(|v| (v.take_or_clone(), false))
}
}
}
#[cfg(not(feature = "no_object"))]
ChainType::Dotting => {
// Check for existence with the Elvis operator
if parent.options().contains(ASTFlags::NEGATED) && target.is_unit() {
return Ok((Dynamic::UNIT, false));
}
match (rhs, new_val, target.is_map()) {
// xxx.fn_name(...) = ???
(Expr::MethodCall(..), Some(..), ..) => {
unreachable!("method call cannot be assigned to")
}
// xxx.fn_name(arg_expr_list)
(Expr::MethodCall(x, pos), None, ..) => {
debug_assert!(
!x.is_qualified(),
"method call in dot chain should not be namespace-qualified"
);
#[cfg(feature = "debugging")]
let reset =
self.run_debugger_with_reset(global, caches, scope, this_ptr, rhs)?;
#[cfg(feature = "debugging")]
defer! { global if Some(reset) => move |g| g.debugger_mut().reset_status(reset) }
let crate::ast::FnCallExpr {
name, hashes, args, ..
} = &**x;
// Truncate the index values upon exit
defer! { idx_values => truncate; let offset = idx_values.len() - args.len(); }
let call_args = &mut idx_values[offset..];
let arg1_pos = args.get(0).map_or(Position::NONE, Expr::position);
self.make_method_call(
global, caches, name, *hashes, target, call_args, arg1_pos, *pos,
)
}
// {xxx:map}.id op= ???
(Expr::Property(x, pos), Some((new_val, op_info)), true) => {
#[cfg(feature = "debugging")]
self.run_debugger(global, caches, scope, this_ptr, rhs)?;
let index = &mut x.2.clone().into();
{
let val_target = &mut self.get_indexed_mut(
global, caches, target, index, *pos, op_pos, true, false,
)?;
self.eval_op_assignment(
global, caches, op_info, root, val_target, new_val,
)?;
}
self.check_data_size(target.source(), op_info.position())?;
Ok((Dynamic::UNIT, true))
}
// {xxx:map}.id
(Expr::Property(x, pos), None, true) => {
#[cfg(feature = "debugging")]
self.run_debugger(global, caches, scope, this_ptr, rhs)?;
let index = &mut x.2.clone().into();
let val = self.get_indexed_mut(
global, caches, target, index, *pos, op_pos, false, false,
)?;
Ok((val.take_or_clone(), false))
}
// xxx.id op= ???
(Expr::Property(x, pos), Some((mut new_val, op_info)), false) => {
#[cfg(feature = "debugging")]
self.run_debugger(global, caches, scope, this_ptr, rhs)?;
let ((getter, hash_get), (setter, hash_set), name) = &**x;
if op_info.is_op_assignment() {
let args = &mut [target.as_mut()];
let (mut orig_val, ..) = self
.exec_native_fn_call(
global, caches, getter, None, *hash_get, args, is_ref_mut, *pos,
)
.or_else(|err| match *err {
// Try an indexer if property does not exist
ERR::ErrorDotExpr(..) => {
let mut prop = name.into();
self.call_indexer_get(
global, caches, target, &mut prop, op_pos,
)
.map(|r| (r, false))
.map_err(|e| {
match *e {
ERR::ErrorIndexingType(..) => err,
_ => e,
}
})
}
_ => Err(err),
})?;
{
let orig_val = &mut (&mut orig_val).into();
self.eval_op_assignment(
global, caches, op_info, root, orig_val, new_val,
)?;
}
new_val = orig_val;
}
let args = &mut [target.as_mut(), &mut new_val];
self.exec_native_fn_call(
global, caches, setter, None, *hash_set, args, is_ref_mut, *pos,
)
.or_else(|err| match *err {
// Try an indexer if property does not exist
ERR::ErrorDotExpr(..) => {
let idx = &mut name.into();
let new_val = &mut new_val;
self.call_indexer_set(
global, caches, target, idx, new_val, is_ref_mut, op_pos,
)
.map_err(|e| match *e {
ERR::ErrorIndexingType(..) => err,
_ => e,
})
}
_ => Err(err),
})
}
// xxx.id
(Expr::Property(x, pos), None, false) => {
#[cfg(feature = "debugging")]
self.run_debugger(global, caches, scope, this_ptr, rhs)?;
let ((getter, hash_get), _, name) = &**x;
let args = &mut [target.as_mut()];
self.exec_native_fn_call(
global, caches, getter, None, *hash_get, args, is_ref_mut, *pos,
)
.map_or_else(
|err| match *err {
// Try an indexer if property does not exist
ERR::ErrorDotExpr(..) => {
let mut prop = name.into();
self.call_indexer_get(global, caches, target, &mut prop, op_pos)
.map(|r| (r, false))
.map_err(|e| match *e {
ERR::ErrorIndexingType(..) => err,
_ => e,
})
}
_ => Err(err),
},
// Assume getters are always pure
|(v, ..)| Ok((v, false)),
)
}
// {xxx:map}.sub_lhs[expr] | {xxx:map}.sub_lhs.expr
(Expr::Index(x, ..) | Expr::Dot(x, ..), new_val, true) => {
let _node = &x.lhs;
let mut _this_ptr = this_ptr;
let _tp = _this_ptr.as_deref_mut();
let val_target = &mut match x.lhs {
Expr::Property(ref p, pos) => {
#[cfg(feature = "debugging")]
self.run_debugger(global, caches, scope, _tp, _node)?;
let index = &mut p.2.clone().into();
self.get_indexed_mut(
global, caches, target, index, pos, op_pos, false, true,
)?
}
// {xxx:map}.fn_name(arg_expr_list)[expr] | {xxx:map}.fn_name(arg_expr_list).expr
Expr::MethodCall(ref x, pos) => {
debug_assert!(
!x.is_qualified(),
"method call in dot chain should not be namespace-qualified"
);
#[cfg(feature = "debugging")]
let reset = self
.run_debugger_with_reset(global, caches, scope, _tp, _node)?;
#[cfg(feature = "debugging")]
defer! { global if Some(reset) => move |g| g.debugger_mut().reset_status(reset) }
let crate::ast::FnCallExpr {
name, hashes, args, ..
} = &**x;
// Truncate the index values upon exit
defer! { idx_values => truncate; let offset = idx_values.len() - args.len(); }
let call_args = &mut idx_values[offset..];
let arg1_pos = args.get(0).map_or(Position::NONE, Expr::position);
self.make_method_call(
global, caches, name, *hashes, target, call_args, arg1_pos, pos,
)?
.0
.into()
}
// Others - syntax error
ref expr => unreachable!("invalid dot expression: {:?}", expr),
};
self.eval_dot_index_chain_raw(
global, caches, scope, _this_ptr, root, rhs, val_target, &x.rhs,
idx_values, new_val,
)
}
// xxx.sub_lhs[expr] | xxx.sub_lhs.expr
(Expr::Index(x, ..) | Expr::Dot(x, ..), new_val, ..) => {
let _node = &x.lhs;
let mut _this_ptr = this_ptr;
let _tp = _this_ptr.as_deref_mut();
match x.lhs {
// xxx.prop[expr] | xxx.prop.expr
Expr::Property(ref p, pos) => {
#[cfg(feature = "debugging")]
self.run_debugger(global, caches, scope, _tp, _node)?;
let ((getter, hash_get), (setter, hash_set), name) = &**p;
let args = &mut [target.as_mut()];
// Assume getters are always pure
let (mut val, ..) = self
.exec_native_fn_call(
global, caches, getter, None, *hash_get, args, is_ref_mut,
pos,
)
.or_else(|err| match *err {
// Try an indexer if property does not exist
ERR::ErrorDotExpr(..) => {
let mut prop = name.into();
self.call_indexer_get(
global, caches, target, &mut prop, op_pos,
)
.map(|r| (r, false))
.map_err(
|e| match *e {
ERR::ErrorIndexingType(..) => err,
_ => e,
},
)
}
_ => Err(err),
})?;
let val = &mut (&mut val).into();
let (result, may_be_changed) = self.eval_dot_index_chain_raw(
global, caches, scope, _this_ptr, root, rhs, val, &x.rhs,
idx_values, new_val,
)?;
// Feed the value back via a setter just in case it has been updated
if may_be_changed {
// Re-use args because the first &mut parameter will not be consumed
let args = &mut [target.as_mut(), val.as_mut()];
// The return value is thrown away and not used.
let _ = self
.exec_native_fn_call(
global, caches, setter, None, *hash_set, args,
is_ref_mut, pos,
)
.or_else(|err| match *err {
// Try an indexer if property does not exist
ERR::ErrorDotExpr(..) => {
let idx = &mut name.into();
let new_val = val;
self.call_indexer_set(
global, caches, target, idx, new_val,
is_ref_mut, op_pos,
)
.or_else(|e| match *e {
// If there is no setter, no need to feed it
// back because the property is read-only
ERR::ErrorIndexingType(..) => {
Ok((Dynamic::UNIT, false))
}
_ => Err(e),
})
}
_ => Err(err),
})?;
}
Ok((result, may_be_changed))
}
// xxx.fn_name(arg_expr_list)[expr] | xxx.fn_name(arg_expr_list).expr
Expr::MethodCall(ref f, pos) => {
debug_assert!(
!f.is_qualified(),
"method call in dot chain should not be namespace-qualified"
);
let val = {
#[cfg(feature = "debugging")]
let reset = self.run_debugger_with_reset(
global, caches, scope, _tp, _node,
)?;
#[cfg(feature = "debugging")]
defer! { global if Some(reset) => move |g| g.debugger_mut().reset_status(reset) }
let crate::ast::FnCallExpr {
name, hashes, args, ..
} = &**f;
// Truncate the index values upon exit
defer! { idx_values => truncate; let offset = idx_values.len() - args.len(); }
let call_args = &mut idx_values[offset..];
let pos1 = args.get(0).map_or(Position::NONE, Expr::position);
self.make_method_call(
global, caches, name, *hashes, target, call_args, pos1, pos,
)?
.0
};
let val = &mut val.into();
self.eval_dot_index_chain_raw(
global, caches, scope, _this_ptr, root, rhs, val, &x.rhs,
idx_values, new_val,
)
}
// Others - syntax error
ref expr => unreachable!("invalid dot expression: {:?}", expr),
}
}
// Syntax error
(expr, ..) => unreachable!("invalid chaining expression: {:?}", expr),
}
}
}
}
}