fix failing lint warnings in beta build

src/forms.rs

@@ -435,7 +435,7 @@ pub(crate) struct Module {
     pub(crate) meta_predicates: MetaPredicateDir,
     pub(crate) extensible_predicates: ExtensiblePredicates,
     pub(crate) local_extensible_predicates: LocalExtensiblePredicates,
-    pub(crate) is_impromptu_module: bool,
+    pub(crate) _is_impromptu_module: bool,
     pub(crate) listing_src: ListingSource,
 }
 
@@ -447,7 +447,7 @@ impl Module {
             code_dir: CodeDir::new(),
             op_dir: default_op_dir(),
             meta_predicates: MetaPredicateDir::new(),
-            is_impromptu_module: false,
+            _is_impromptu_module: false,
             extensible_predicates: ExtensiblePredicates::new(),
             local_extensible_predicates: LocalExtensiblePredicates::new(),
             listing_src,
@@ -460,7 +460,7 @@ impl Module {
             code_dir: CodeDir::new(),
             op_dir: OpDir::new(),
             meta_predicates: MetaPredicateDir::new(),
-            is_impromptu_module: false,
+            _is_impromptu_module: false,
             extensible_predicates: ExtensiblePredicates::new(),
             local_extensible_predicates: LocalExtensiblePredicates::new(),
             listing_src: ListingSource::DynamicallyGenerated,

src/heap_print.rs

@@ -339,7 +339,7 @@ pub(crate) struct HCPrinter<'a, Outputter> {
     state_stack: Vec<TokenOrRedirect>,
     toplevel_spec: Option<DirectedOp>,
     heap_locs: ReverseHeapVarDict,
-    printed_vars: IndexSet<Addr>,
+    _printed_vars: IndexSet<Addr>,
     last_item_idx: usize,
     cyclic_terms: IndexMap<Addr, usize>,
     non_cyclic_terms: IndexSet<usize>,
@@ -348,7 +348,7 @@ pub(crate) struct HCPrinter<'a, Outputter> {
     pub(crate) numbervars: bool,
     pub(crate) quoted: bool,
     pub(crate) ignore_ops: bool,
-    pub(crate) print_strings_as_strs: bool,
+    pub(crate) _print_strings_as_strs: bool,
     pub(crate) max_depth: usize,
 }
 
@@ -466,7 +466,7 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter> {
             state_stack: vec![],
             heap_locs: ReverseHeapVarDict::new(),
             toplevel_spec: None,
-            printed_vars: IndexSet::new(),
+            _printed_vars: IndexSet::new(),
             last_item_idx: 0,
             numbervars: false,
             numbervars_offset: Integer::from(0),
@@ -475,7 +475,7 @@ impl<'a, Outputter: HCValueOutputter> HCPrinter<'a, Outputter> {
             cyclic_terms: IndexMap::new(),
             non_cyclic_terms: IndexSet::new(),
             var_names: IndexMap::new(),
-            print_strings_as_strs: false,
+            _print_strings_as_strs: false,
             max_depth: 0,
         }
     }

src/machine/mod.rs

@@ -109,7 +109,7 @@ impl LoadContext {
 #[derive(Debug)]
 pub struct Machine {
     pub(super) machine_st: MachineState,
-    pub(super) inner_heap: Heap,
+    pub(super) _inner_heap: Heap,
     pub(super) policies: MachinePolicies,
     pub(super) indices: IndexStore,
     pub(super) code_repo: CodeRepo,
@@ -280,7 +280,7 @@ impl Machine {
 
         let mut wam = Machine {
             machine_st: MachineState::new(),
-            inner_heap: Heap::new(),
+            _inner_heap: Heap::new(),
             policies: MachinePolicies::new(),
             indices: IndexStore::new(),
             code_repo: CodeRepo::new(),

src/machine/preprocessor.rs

@@ -553,14 +553,14 @@ fn qualified_clause_to_query_term<'a>(
 
 #[derive(Debug)]
 pub(crate) struct Preprocessor {
-    flags: MachineFlags,
+    _flags: MachineFlags,
     queue: VecDeque<VecDeque<Term>>,
 }
 
 impl Preprocessor {
     pub(super) fn new(flags: MachineFlags) -> Self {
         Preprocessor {
-            flags,
+            _flags: flags,
             queue: VecDeque::new(),
         }
     }

src/machine/stack.rs

@@ -109,7 +109,7 @@ pub(crate) struct OrFramePrelude {
     pub(crate) b: usize,
     pub(crate) bp: LocalCodePtr,
     pub(crate) tr: usize,
-    pub(crate) pstr_tr: usize,
+    pub(crate) _pstr_tr: usize,
     pub(crate) h: usize,
     pub(crate) b0: usize,
 }