Loop word

crates/forth/src/ops.rs

@@ -80,4 +80,5 @@ pub enum Op {
     Range,
     Noise,
     Chain,
+    Loop,
 }

crates/forth/src/vm.rs

@@ -647,6 +647,13 @@ impl Forth {
                     }
                 }
 
+                Op::Loop => {
+                    let beats = stack.pop().ok_or("stack underflow")?.as_float()?;
+                    let dur = beats * 60.0 / ctx.tempo / ctx.speed;
+                    cmd.set_param("fit".into(), dur.to_string());
+                    cmd.set_param("dur".into(), dur.to_string());
+                }
+
                 Op::ListStart => {
                     stack.push(Value::Marker);
                 }

crates/forth/src/words.rs

@@ -614,6 +614,13 @@ pub const WORDS: &[Word] = &[
         example: "{ emit } 3 div for",
         compile: Simple,
     },
+    Word {
+        name: "loop",
+        stack: "(n --)",
+        desc: "Fit sample to n beats",
+        example: "\"break\" s 4 loop emit",
+        compile: Simple,
+    },
     Word {
         name: "|",
         stack: "(-- marker)",
@@ -1565,6 +1572,7 @@ pub(super) fn simple_op(name: &str) -> Option<Op> {
         "range" => Op::Range,
         "noise" => Op::Noise,
         "chain" => Op::Chain,
+        "loop" => Op::Loop,
         _ => return None,
     })
 }