1 files changed, 12 insertions, 4 deletions
diff --git a/src/lazy_buffer.rs b/src/lazy_buffer.rs
index 01123d4..fa514ec 100644
--- a/src/lazy_buffer.rs
+++ b/src/lazy_buffer.rs
@@ -1,4 +1,5 @@
 use std::ops::Index;
+use alloc::vec::Vec;
 
 #[derive(Debug, Clone)]
 pub struct LazyBuffer<I: Iterator> {
@@ -23,10 +24,6 @@ where
         self.buffer.len()
     }
 
-    pub fn is_done(&self) -> bool {
-        self.done
-    }
-
     pub fn get_next(&mut self) -> bool {
         if self.done {
             return false;
@@ -43,6 +40,17 @@ where
             }
         }
     }
+
+    pub fn prefill(&mut self, len: usize) {
+        let buffer_len = self.buffer.len();
+
+        if !self.done && len > buffer_len {
+            let delta = len - buffer_len;
+
+            self.buffer.extend(self.it.by_ref().take(delta));
+            self.done = self.buffer.len() < len;
+        }
+    }
 }
 
 impl<I, J> Index<J> for LazyBuffer<I>