Add example of OwningRows using self_cell

This commit is contained in:
gwenn 2024-09-29 16:06:36 +02:00
parent 70d192d3cd
commit 93787c6855
2 changed files with 28 additions and 0 deletions

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@ -146,6 +146,7 @@ regex = "1.5.5"
uuid = { version = "1.0", features = ["v4"] }
unicase = "2.6.0"
ouroboros = "0.18"
self_cell = { git = "https://github.com/Voultapher/self_cell.git" }
# Use `bencher` over criterion because it builds much faster,
# and we don't have many benchmarks
bencher = "0.1"

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@ -0,0 +1,27 @@
extern crate rusqlite;
use rusqlite::{CachedStatement, Connection, Result, Rows};
use self_cell::{self_cell, MutBorrow};
type RowsRef<'a> = Rows<'a>;
self_cell!(
struct OwningRows<'conn> {
owner: MutBorrow<CachedStatement<'conn>>,
#[covariant]
dependent: RowsRef,
}
);
fn main() -> Result<()> {
let conn = Connection::open_in_memory()?;
let stmt = conn.prepare_cached("SELECT 1")?;
let mut or = OwningRows::try_new(MutBorrow::new(stmt), |s| s.borrow_mut().query([]))?;
or.with_dependent_mut(|_stmt, rows| -> Result<()> {
while let Some(row) = rows.next()? {
assert_eq!(Ok(1), row.get(0));
}
Ok(())
})?;
Ok(())
}