Add example for custom bindings

- Extend Meta-F,Alt+Right feature for hint partial completion
kkawakam · Mar 6, 2021 · 3d692d3 · 3d692d3
1 parent bf5bbfd
commit 3d692d3
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Showing 3 changed files with 33 additions and 23 deletions.
diff --git a/examples/custom_key_bindings.rs b/examples/custom_key_bindings.rs
@@ -37,14 +37,24 @@ impl Highlighter for MyHelper {
     }
 }
 
+#[derive(Clone)]
 struct CompleteHintHandler;
 impl ConditionalEventHandler for CompleteHintHandler {
     fn handle(&self, evt: &Event, _: RepeatCount, _: bool, ctx: &EventContext) -> Option<Cmd> {
-        debug_assert_eq!(*evt, Event::from(KeyEvent::ctrl('E')));
-        if ctx.has_hint() {
-            Some(Cmd::CompleteHint)
+        if !ctx.has_hint() {
+            return None; // default
+        }
+        if let Some(k) = evt.get(0) {
+            #[allow(clippy::if_same_then_else)]
+            if *k == KeyEvent::ctrl('E') {
+                Some(Cmd::CompleteHint)
+            } else if *k == KeyEvent::alt('f') && ctx.line().len() == ctx.pos() {
+                Some(Cmd::CompleteHint) // TODO give access to hint
+            } else {
+                None
+            }
         } else {
-            None // default
+            unreachable!()
         }
     }
 }
@@ -71,10 +81,9 @@ fn main() {
     let mut rl = Editor::<MyHelper>::new();
     rl.set_helper(Some(MyHelper(HistoryHinter {})));
 
-    rl.bind_sequence(
-        KeyEvent::ctrl('E'),
-        EventHandler::Conditional(Box::new(CompleteHintHandler)),
-    );
+    let ceh = Box::new(CompleteHintHandler);
+    rl.bind_sequence(KeyEvent::ctrl('E'), EventHandler::Conditional(ceh.clone()));
+    rl.bind_sequence(KeyEvent::alt('f'), EventHandler::Conditional(ceh));
     rl.bind_sequence(
         KeyEvent::from('\t'),
         EventHandler::Conditional(Box::new(TabEventHandler)),

diff --git a/examples/numeric_input.rs b/examples/numeric_input.rs
@@ -6,22 +6,14 @@ use rustyline::{
 struct FilteringEventHandler;
 impl ConditionalEventHandler for FilteringEventHandler {
     fn handle(&self, evt: &Event, _: RepeatCount, _: bool, _: &EventContext) -> Option<Cmd> {
-        match evt {
-            Event::KeySeq(ks) => {
-                if let Some(KeyEvent(KeyCode::Char(c), m)) = ks.first() {
-                    if m.contains(Modifiers::CTRL)
-                        || m.contains(Modifiers::ALT)
-                        || c.is_ascii_digit()
-                    {
-                        None
-                    } else {
-                        Some(Cmd::Noop) // filter out invalid input
-                    }
-                } else {
-                    None
-                }
+        if let Some(KeyEvent(KeyCode::Char(c), m)) = evt.get(0) {
+            if m.contains(Modifiers::CTRL) || m.contains(Modifiers::ALT) || c.is_ascii_digit() {
+                None
+            } else {
+                Some(Cmd::Noop) // filter out invalid input
             }
-            _ => None,
+        } else {
+            None
         }
     }
 }

diff --git a/src/binding.rs b/src/binding.rs
@@ -29,6 +29,15 @@ impl Event {
         }
         self
     }
+
+    /// Return `i`th key event
+    pub fn get(&self, i: usize) -> Option<&KeyEvent> {
+        if let Event::KeySeq(ref ks) = self {
+            ks.get(i)
+        } else {
+            None
+        }
+    }
 }
 
 impl From<KeyEvent> for Event {