From 6801f46b19fccd2c411351bca97b395fe2e0e606 Mon Sep 17 00:00:00 2001
From: David Ellis <isv.damocles@gmail.com>
Date: Wed, 31 Jul 2024 16:18:35 -0500
Subject: [PATCH] Implement the `Array` `store` and `delete` functions and the
 `Buffer` `store` function (#825)

---
 src/compile/integration_tests.rs | 20 +++++++++++++
 src/std/root.ln                  |  3 ++
 src/std/root.rs                  | 50 ++++++++++++++++++++++++++++++++
 3 files changed, 73 insertions(+)

diff --git a/src/compile/integration_tests.rs b/src/compile/integration_tests.rs
index 6f8fb1c6a..5c0914c48 100644
--- a/src/compile/integration_tests.rs
+++ b/src/compile/integration_tests.rs
@@ -1918,6 +1918,17 @@ concat test
 1, 1, 2, 3, 5, 8, 4, 5, 6
 "#;
 );
+test!(array_store_and_delete => r#"
+    export fn main {
+        const test = [ 1, 2, 5 ];
+        test.store(2, 3);
+        test.store(3, 4);
+        test.print;
+        test.delete(4).print;
+        test.print;
+    }"#;
+    stdout "[1, 2, 3, 4, 5]\n5\n[1, 2, 3, 4]\n";
+);
 test!(array_custom_types => r#"
     type Foo =
       foo: string,
@@ -2004,6 +2015,15 @@ test!(buffer_repeat => r#"
     }"#;
     stdout "1, 2, 3, 1, 2, 3, 1, 2, 3\n";
 );
+test!(buffer_store => r#"
+    export fn main {
+        let buf = {i64[3]}(1, 2, 5);
+        print(buf);
+        buf.store(2, 3).print;
+        print(buf);
+    }"#;
+    stdout "[1, 2, 5]\n5\n[1, 2, 3]\n";
+);
 
 // Hashing
 test!(hash => r#"
diff --git a/src/std/root.ln b/src/std/root.ln
index 5b74c12f0..c81f4635b 100644
--- a/src/std/root.ln
+++ b/src/std/root.ln
@@ -583,6 +583,8 @@ export fn has{T}(a: Array{T}, f: (T) -> bool) -> bool binds hasfnarray;
 export fn find{T}(a: Array{T}, f: (T) -> bool) -> Maybe{T} binds findarray;
 export fn every{T}(a: Array{T}, f: (T) -> bool) -> bool binds everyarray;
 export fn repeat{T}(a: Array{T}, c: i64) -> Array{T} binds repeatarray;
+export fn store{T}(a: Array{T}, i: i64, v: T) -> Fallible{void} binds storearray;
+export fn delete{T}(a: Array{T}, i: i64) -> Fallible{T} binds deletearray;
 
 /// Buffer related bindings
 export fn get{T, S}(b: T[S], i: i64) -> Maybe{T} binds getbuffer;
@@ -608,6 +610,7 @@ export fn concat{T, S, N}(a: Buffer{T, S}, b: Buffer{T, N}) -> Buffer{T, S + N}
 // TODO: Be able to resolve explicit integer constant values as the integer type so it can be
 // grabbed by the type inference system. For now, repeat for buffers outputs an array, instead.
 export fn repeat{T, S}(b: Buffer{T, S}, c: i64) -> Array{T} binds repeatbuffertoarray;
+export fn store{T, S}(b: Buffer{T, S}, i: i64, v: T) -> Fallible{T} binds storebuffer;
 
 /// Dictionary-related bindings
 export fn Dict{K, V}() -> Dict{K, V} binds newdict;
diff --git a/src/std/root.rs b/src/std/root.rs
index 930a95099..2f4ad34e3 100644
--- a/src/std/root.rs
+++ b/src/std/root.rs
@@ -2870,6 +2870,38 @@ fn repeatarray<T: std::clone::Clone>(a: &Vec<T>, c: &i64) -> Vec<T> {
     out
 }
 
+/// `storearray` inserts a new value at the specified index, but fails if the index is greater than
+/// the length of the length of the array (so there would be at least one "gap" in the array in
+/// that situation)
+#[inline(always)]
+fn storearray<T: std::clone::Clone>(a: &mut Vec<T>, i: &i64, v: &T) -> Result<(), AlanError> {
+    match (*i as usize) > a.len() {
+        true => Err(format!(
+            "Provided array index {} is greater than the length of the array",
+            i
+        )
+        .into()),
+        false => {
+            a.insert(*i as usize, v.clone());
+            Ok(())
+        }
+    }
+}
+
+/// `deletearray` deletes a value at the specified index, but fails if the index is out-of-bounds.
+/// If it succeeds, it returns the value wrapped in a Fallible.
+#[inline(always)]
+fn deletearray<T: std::clone::Clone>(a: &mut Vec<T>, i: &i64) -> Result<T, AlanError> {
+    match (*i as usize) >= a.len() {
+        true => Err(format!(
+            "Provided array index {} is beyond the bounds of the array",
+            i
+        )
+        .into()),
+        false => Ok(a.remove(*i as usize).clone()),
+    }
+}
+
 /// Buffer-related functions
 
 /// `getbuffer` returns the value at the given index presuming it exists
@@ -3007,6 +3039,24 @@ fn repeatbuffertoarray<T: std::clone::Clone, const S: usize>(a: &[T; S], c: &i64
     out
 }
 
+/// `storebuffer` stores the provided value in the specified index. If the index is out-of-bounds
+/// for the buffer it fails, otherwise it returns the old value.
+#[inline(always)]
+fn storebuffer<T: std::clone::Clone, const S: usize>(
+    a: &mut [T; S],
+    i: &i64,
+    v: &T,
+) -> Result<T, AlanError> {
+    match (*i as usize) < a.len() {
+        false => Err(format!(
+            "The provided index {} is out-of-bounds for the specified buffer",
+            i
+        )
+        .into()),
+        true => Ok(std::mem::replace(a.each_mut()[*i as usize], v.clone())),
+    }
+}
+
 /// Dictionary-related bindings
 
 /// `newdict` creates a new dictionary