support filtering based on bool filters

Cargo.toml

@@ -20,5 +20,6 @@ all-features = true
 rustdoc-args = ["--cfg", "docsrs"]
 
 [dependencies]
+bitvec = "1.0.1"
 hashbrown = "0.14.3"
 venndb-macros = { version = "0.1.0", path = "venndb-macros" }

src/lib.rs

@@ -1,9 +1,10 @@
 pub use venndb_macros::VennDB;
 
 #[doc(hidden)]
-pub mod internal {
+pub mod __internal {
     //! Hidden thirdparty dependencies for venndb,
     //! not to be relied upon directly, as they may change at any time.
 
+    pub use bitvec::{bitvec, order::Lsb0, slice::IterOnes, vec::BitVec};
     pub use hashbrown::HashMap;
 }

venndb-macros/src/field.rs

@@ -23,6 +23,7 @@ pub struct StructField<'a> {
 
 pub enum FieldInfo<'a> {
     Key(KeyField<'a>),
+    Filter(FilterField<'a>),
 }
 
 pub struct KeyField<'a> {
@@ -48,6 +49,24 @@ impl<'a> KeyField<'a> {
     }
 }
 
+pub struct FilterField<'a> {
+    pub name: &'a Ident,
+}
+
+impl<'a> FilterField<'a> {
+    pub fn name(&'a self) -> &'a Ident {
+        self.name
+    }
+
+    pub fn filter_name(&self) -> Ident {
+        format_ident!("filter_{}", self.name)
+    }
+
+    pub fn filter_not_name(&self) -> Ident {
+        format_ident!("filter_not_{}", self.name)
+    }
+}
+
 impl<'a> StructField<'a> {
     /// Attempts to parse a field of a `#[derive(VennDB)]` struct, pulling out the
     /// fields required for code generation.
@@ -63,6 +82,7 @@ impl<'a> StructField<'a> {
                 name: self.name,
                 ty: &self.field.ty,
             }),
+            FieldKind::Filter => FieldInfo::Filter(FilterField { name: self.name }),
         })
     }
 }