From 4f5758c9836d268c5adbb8474cea207582b558cb Mon Sep 17 00:00:00 2001
From: Aayush Sabharwal <aayush.sabharwal@juliahub.com>
Date: Wed, 21 Feb 2024 17:48:47 +0530
Subject: [PATCH] feat: add support for inplace getp

---
 src/parameter_indexing.jl       | 18 ++++++++++++++----
 test/parameter_indexing_test.jl | 12 ++++++++++++
 2 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/src/parameter_indexing.jl b/src/parameter_indexing.jl
index eaa5f2c..b58fb79 100644
--- a/src/parameter_indexing.jl
+++ b/src/parameter_indexing.jl
@@ -57,8 +57,10 @@ end
 
 function _getp(sys, ::ScalarSymbolic, ::SymbolicTypeTrait, p)
     idx = parameter_index(sys, p)
-    return function getter(sol)
-        return parameter_values(sol, idx)
+    return let idx = idx
+        function getter(sol)
+            return parameter_values(sol, idx)
+        end
     end
 end
 
@@ -70,8 +72,16 @@ for (t1, t2) in [
     @eval function _getp(sys, ::NotSymbolic, ::$t1, p::$t2)
         getters = getp.((sys,), p)
 
-        return function getter(sol)
-            map(g -> g(sol), getters)
+        return let getters = getters
+            function getter(sol)
+                map(g -> g(sol), getters)
+            end
+            function getter(buffer, sol)
+                for (i, g) in zip(eachindex(buffer), getters)
+                    buffer[i] = g(sol)
+                end
+                buffer
+            end
         end
     end
 end
diff --git a/test/parameter_indexing_test.jl b/test/parameter_indexing_test.jl
index a2646f8..adac52f 100644
--- a/test/parameter_indexing_test.jl
+++ b/test/parameter_indexing_test.jl
@@ -56,3 +56,15 @@ for (sym, oldval, newval, check_inference) in [
     set!(p, oldval)
     @test get(p) == oldval
 end
+
+for (sym, val) in [
+    ([:a, :b, :c], p),
+    ([:c, :a], p[[3, 1]]),
+    ((:b, :a), p[[2, 1]]),
+    ((1, :c), p[[1, 3]])
+]
+    buffer = zeros(length(sym))
+    get = getp(sys, sym)
+    @inferred get(buffer, fi)
+    @test buffer == val
+end