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throw errors on cyclic terms when evaluating is/2 expressions

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This commit is contained in:
Mark Thom
2022-04-07 23:06:58 -06:00
parent 064bfa5e0d
commit 85b4f235ef
1 changed files with 12 additions and 6 deletions
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18
src/machine/arithmetic_ops.rs
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@@ -1102,24 +1102,30 @@ impl MachineState {
while let Some(value) = iter.next() {
if value.get_forwarding_bit() {
std::mem::drop(iter);
let (name, arity) = read_heap_cell!(value,
(HeapCellValueTag::Atom, (name, arity)) => {
(name, arity)
}
(HeapCellValueTag::Lis | HeapCellValueTag::PStr) => {
(HeapCellValueTag::Str, s) => {
cell_as_atom_cell!(self.heap[s]).get_name_and_arity()
}
(HeapCellValueTag::Lis | HeapCellValueTag::PStr | HeapCellValueTag::PStrOffset |
HeapCellValueTag::PStrLoc) => {
(atom!("."), 2)
}
(HeapCellValueTag::AttrVar | HeapCellValueTag::Var) => {
let err = self.instantiation_error();
return Err(self.error_form(err, stub_gen()));
}
_ => {
unreachable!()
}
);
std::mem::drop(iter);
let evaluable_error = self.evaluable_error(name, arity);
let stub = stub_gen();
return Err(self.error_form(evaluable_error, stub));
return Err(self.error_form(evaluable_error, stub_gen()));
}
read_heap_cell!(value,