From 808aeea11c74196265d3ea2dfcc7c66d76826daa Mon Sep 17 00:00:00 2001
From: Rich FitzJohn <r.fitzjohn@imperial.ac.uk>
Date: Wed, 6 Nov 2024 15:40:03 +0000
Subject: [PATCH 1/2] Add helpers for validating ranges

---
 inst/include/dust2/common.hpp    |  9 +++++++
 inst/include/dust2/r/helpers.hpp | 40 ++++++++++++++++++++++++++++++++
 2 files changed, 49 insertions(+)

diff --git a/inst/include/dust2/common.hpp b/inst/include/dust2/common.hpp
index 16d4a801..937895d7 100644
--- a/inst/include/dust2/common.hpp
+++ b/inst/include/dust2/common.hpp
@@ -55,6 +55,15 @@ void read_dimensions(cpp11::list args, const char * name, dust2::array::dimensio
 template <>
 void read_dimensions(cpp11::list args, const char * name, dust2::array::dimensions<1>& dest);
 
+template <typename T>
+void check_min_array(const std::vector<T>& x, const T min, const char * name);
+template <typename T>
+void check_max_array(const std::vector<T>& x, const T min, const char * name);
+template <typename T>
+void check_min_scalar(const T x, const T min, const char * name);
+template <typename T>
+void check_max_scalar(const T x, const T min, const char * name);
+
 }
 
 }
diff --git a/inst/include/dust2/r/helpers.hpp b/inst/include/dust2/r/helpers.hpp
index 9e5dc946..8f9eaec9 100644
--- a/inst/include/dust2/r/helpers.hpp
+++ b/inst/include/dust2/r/helpers.hpp
@@ -582,6 +582,46 @@ void read_int_array(cpp11::list args, const dust2::array::dimensions<rank>& dim,
   }
 }
 
+template <typename T>
+void check_min_array(const std::vector<T>& x, const T min, const char * name) {
+  for (size_t i = 0; i < x.size(); ++i) {
+    if (x[i] < min) {
+      const auto min_str = std::to_string(min);
+      cpp11::stop("All values of '%s' must be at least %s",
+                  name, min_str.c_str());
+    }
+  }
+}
+
+template <typename T>
+void check_max_array(const std::vector<T>& x, const T max, const char * name) {
+  for (size_t i = 0; i < x.size(); ++i) {
+    if (x[i] > max) {
+      const auto max_str = std::to_string(max);
+      cpp11::stop("All values of '%s' must be at most %s",
+                  name, max_str.c_str());
+    }
+  }
+}
+
+template <typename T>
+void check_min_scalar(const T x, const T min, const char * name) {
+  if (x[i] < min) {
+    const auto min_str = std::to_string(min);
+    cpp11::stop("'%s' must be at least %s",
+                name, min_str.c_str());
+  }
+}
+
+template <typename T>
+void check_max_scalar(const T x, const T max, const char * name) {
+  if (x[i] > max) {
+    const auto max_str = std::to_string(max);
+    cpp11::stop("'%s' must be at most %s",
+                name, max_str.c_str());
+  }
+}
+
 inline cpp11::sexp packing_to_r(const dust2::packing& packing_info) {
   if (packing_info.size() == 0) {
     return R_NilValue;

From 0caeec1e94ea0dd0bdac5afcdbf6b4a082dddd34 Mon Sep 17 00:00:00 2001
From: Rich FitzJohn <r.fitzjohn@imperial.ac.uk>
Date: Thu, 7 Nov 2024 08:00:11 +0000
Subject: [PATCH 2/2] Fix helpers

---
 inst/include/dust2/r/helpers.hpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/inst/include/dust2/r/helpers.hpp b/inst/include/dust2/r/helpers.hpp
index 8f9eaec9..42df4522 100644
--- a/inst/include/dust2/r/helpers.hpp
+++ b/inst/include/dust2/r/helpers.hpp
@@ -606,7 +606,7 @@ void check_max_array(const std::vector<T>& x, const T max, const char * name) {
 
 template <typename T>
 void check_min_scalar(const T x, const T min, const char * name) {
-  if (x[i] < min) {
+  if (x < min) {
     const auto min_str = std::to_string(min);
     cpp11::stop("'%s' must be at least %s",
                 name, min_str.c_str());
@@ -615,7 +615,7 @@ void check_min_scalar(const T x, const T min, const char * name) {
 
 template <typename T>
 void check_max_scalar(const T x, const T max, const char * name) {
-  if (x[i] > max) {
+  if (x > max) {
     const auto max_str = std::to_string(max);
     cpp11::stop("'%s' must be at most %s",
                 name, max_str.c_str());