lib: improve base example

src/lib.rs

@@ -1,18 +1,15 @@
 use sqlite3_ext::{
-    function::{Context, FunctionOptions},
-    *,
+    Connection, FromValue, Result, ValueRef, ValueType,
+    function::Context,
+    sqlite3_ext_fn, sqlite3_ext_main,
 };
 
 fn add(a: i32, b: i32) -> i32 {
     a + b
 }
 
+#[sqlite3_ext_fn(n_args = 2, deterministic)]
 fn add_sqlite(ctx: &mut Context, args: &mut [&mut ValueRef]) -> Result<()> {
-    if args.len() != 2 {
-        return Err(sqlite3_ext::Error::Module(
-            "myadd requires exactly 2 arguments".to_string(),
-        ));
-    }
     if args[0].value_type() != ValueType::Integer || args[1].value_type() != ValueType::Integer {
         return Err(sqlite3_ext::Error::Module(
             "myadd requires both arguments to be an integer".to_string(),
@@ -28,13 +25,7 @@ fn add_sqlite(ctx: &mut Context, args: &mut [&mut ValueRef]) -> Result<()> {
 
 #[sqlite3_ext_main(persistent)]
 fn init(db: &Connection) -> Result<()> {
-    db.create_scalar_function(
-        "myadd",
-        &FunctionOptions::default()
-            .set_n_args(2)
-            .set_deterministic(true),
-        add_sqlite,
-    )?;
+    db.create_scalar_function("myadd", &ADD_SQLITE_OPTS, add_sqlite)?;
 
     Ok(())
 }
@@ -42,7 +33,7 @@ fn init(db: &Connection) -> Result<()> {
 #[cfg(all(test, feature = "static"))]
 mod test {
     use super::*;
-    use sqlite3_ext::Error;
+    use sqlite3_ext::{Database, Error, FallibleIterator, FallibleIteratorMut};
 
     fn setup() -> Result<Database> {
         let conn = Database::open(":memory:")?;