Feat: add slicing words

crates/forth/src/words/compile.rs

@@ -58,7 +58,7 @@ pub(super) fn simple_op(name: &str) -> Option<Op> {
         "nand" => Op::Nand,
         "nor" => Op::Nor,
         "ifelse" => Op::IfElse,
-        "pick" => Op::Pick,
+        "select" => Op::Pick,
         "sound" => Op::NewCmd,
         "." => Op::Emit,
         "rand" => Op::Rand(None),

crates/forth/src/words/core.rs

@@ -507,12 +507,12 @@ pub(super) const WORDS: &[Word] = &[
         varargs: false,
     },
     Word {
-        name: "pick",
+        name: "select",
         aliases: &[],
         category: "Logic",
         stack: "(..quots n --)",
         desc: "Execute nth quotation (0-indexed)",
-        example: "{ 1 } { 2 } { 3 } 2 pick => 3",
+        example: "{ 1 } { 2 } { 3 } 2 select => 3",
         compile: Simple,
         varargs: true,
     },

crates/forth/src/words/sound.rs

@@ -186,6 +186,26 @@ pub(super) const WORDS: &[Word] = &[
         compile: Param,
         varargs: true,
     },
+    Word {
+        name: "slice",
+        aliases: &[],
+        category: "Sample",
+        stack: "(v.. --)",
+        desc: "Divide sample into N equal slices",
+        example: r#""break" s 8 slice 3 pick ."#,
+        compile: Param,
+        varargs: true,
+    },
+    Word {
+        name: "pick",
+        aliases: &[],
+        category: "Sample",
+        stack: "(v.. --)",
+        desc: "Select which slice to play (0-indexed, wraps)",
+        example: r#""break" s 8 slice 3 pick ."#,
+        compile: Param,
+        varargs: true,
+    },
     Word {
         name: "voice",
         aliases: &[],

docs/forth/control_flow.md

@@ -63,12 +63,12 @@ Reads naturally: "c3 or c4, depending on the coin."
 tri s c4 note 0.2 decay .      ;; loud during fills, quiet otherwise
 ```
 
-## pick
+## select
 
 Choose the nth option from a list of quotations:
 
 ```forth
-{ c4 } { e4 } { g4 } { b4 } iter 4 mod pick
+{ c4 } { e4 } { g4 } { b4 } iter 4 mod select
 note sine s 0.5 decay .
 ```
 

tests/forth/comparison.rs

@@ -196,21 +196,21 @@ fn ifelse_false() {
 }
 
 #[test]
-fn pick_first() {
-    expect_int("{ 10 } { 20 } { 30 } 0 pick", 10);
+fn select_first() {
+    expect_int("{ 10 } { 20 } { 30 } 0 select", 10);
 }
 
 #[test]
-fn pick_second() {
-    expect_int("{ 10 } { 20 } { 30 } 1 pick", 20);
+fn select_second() {
+    expect_int("{ 10 } { 20 } { 30 } 1 select", 20);
 }
 
 #[test]
-fn pick_third() {
-    expect_int("{ 10 } { 20 } { 30 } 2 pick", 30);
+fn select_third() {
+    expect_int("{ 10 } { 20 } { 30 } 2 select", 30);
 }
 
 #[test]
-fn pick_preserves_stack() {
-    expect_int("5 { 10 } { 20 } 0 pick +", 15);
+fn select_preserves_stack() {
+    expect_int("5 { 10 } { 20 } 0 select +", 15);
 }

tests/forth/sound.rs

@@ -255,3 +255,16 @@ fn all_replaces_previous_global() {
     assert_eq!(outputs.len(), 1);
     assert!(outputs[0].contains("lpf/2000"), "latest lpf should be 2000: {}", outputs[0]);
 }
+
+#[test]
+fn slice_param() {
+    let outputs = expect_outputs(r#""break" s 8 slice ."#, 1);
+    assert!(outputs[0].contains("slice/8"));
+}
+
+#[test]
+fn pick_param() {
+    let outputs = expect_outputs(r#""break" s 8 slice 3 pick ."#, 1);
+    assert!(outputs[0].contains("slice/8"));
+    assert!(outputs[0].contains("pick/3"));
+}