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programs/7-bump-seed-canonicalization/recommended/src/lib.rs

@@ -15,12 +15,21 @@ pub mod bump_seed_canonicalization_recommended {
 #[derive(Accounts)]
 #[instruction(key: u64)]
 pub struct BumpSeed<'info> {
-    #[account(seeds = [key.to_le_bytes().as_ref()], bump = data.bump)]
+    // Note a subtle pattern that is not displayed here.
+    //
+    // Usually, the usage of PDAs is broken into two parts:
+    //
+    // 1) allocation via `#[account(init, seeds = [...], bump)]`
+    // 2) using the account via `#[account(init, seeds = [...], bump = data.bump)]
+    //
+    // When using a PDA, it's usually recommend to store the bump seed in the
+    // account data, so that you can use it as demonstrated in 2), which will
+    // provide a more efficient check.
+    #[account(seeds = [key.to_le_bytes().as_ref()], bump)]
     data: Account<'info, Data>,
 }
 
 #[account]
 pub struct Data {
     value: u64,
-    bump: u8,
 }