From 1fe9d57068e61e30dbb999f9979acae1ffcbab28 Mon Sep 17 00:00:00 2001
From: Aayush Sabharwal <aayush.sabharwal@juliahub.com>
Date: Fri, 20 Oct 2023 21:39:15 +0530
Subject: [PATCH] feat: add pre-1.9 compat using Requires

---
 Project.toml                     | 4 ++++
 src/SymbolicIndexingInterface.jl | 7 +++++++
 2 files changed, 11 insertions(+)

diff --git a/Project.toml b/Project.toml
index 19f2bb91..36da873b 100644
--- a/Project.toml
+++ b/Project.toml
@@ -3,6 +3,9 @@ uuid = "2efcf032-c050-4f8e-a9bb-153293bab1f5"
 authors = ["Aayush Sabharwal <aayush.sabharwal@gmail.com> and contributors"]
 version = "0.3.0"
 
+[deps]
+Requires = "ae029012-a4dd-5104-9daa-d747884805df"
+
 [weakdeps]
 SymbolicUtils = "d1185830-fcd6-423d-90d6-eec64667417b"
 Symbolics = "0c5d862f-8b57-4792-8d23-62f2024744c7"
@@ -12,6 +15,7 @@ SymbolicIndexingInterfaceSymbolicUtilsExt = "SymbolicUtils"
 SymbolicIndexingInterfaceSymbolicsExt = "Symbolics"
 
 [compat]
+Requires = "1.0"
 SymbolicUtils = "1.4"
 Symbolics = "5.10"
 julia = "1"
diff --git a/src/SymbolicIndexingInterface.jl b/src/SymbolicIndexingInterface.jl
index f2f2013f..cbaf9d36 100644
--- a/src/SymbolicIndexingInterface.jl
+++ b/src/SymbolicIndexingInterface.jl
@@ -7,5 +7,12 @@ export issymbolic, isvariable, variableindex, isparameter, parameterindex,
     isindependent_variable, isobserved, observed, istimedependent, constant_structure
 include("interface.jl")
 
+@static if !isdefined(Base, :get_extension)
+    using Requires
+    function __init__()
+        @require Symbolics="0c5d862f-8b57-4792-8d23-62f2024744c7" include("../ext/SymbolicIndexingInterfaceSymbolicsExt.jl")
+        @require SymbolicUtils="d1185830-fcd6-423d-90d6-eec64667417b" include("../ext/SymbolicIndexingInterfaceSymbolicUtilsExt.jl")
+    end
+end
 
 end