diff --git a/lib.c b/lib.c
index a441b0e..e439b5a 100644
--- a/lib.c
+++ b/lib.c
@@ -1757,6 +1757,41 @@ static void get_size_array(struct context* ctx) {
 	ink_push(ctx, sz);
 }
 
+static void is_array(struct context* ctx) {
+	int tid;
+	struct ink_routine *currentRoutine;
+	struct elem a;
+	
+	tid = get_type_by_name(ctx, "array");
+	currentRoutine = ctx->routines + ctx->routine_current;
+	if (currentRoutine->top < 1) {
+		currentRoutine->panic = -1;
+		return;
+	}
+	a.type = INK_INTEGER;
+	a.value = currentRoutine->stack[currentRoutine->top - 1].type == tid;
+	ink_pop(ctx);
+	
+	ink_push(ctx, a);
+}
+
+static void is_int(struct context* ctx) {
+	int tid;
+	struct ink_routine *currentRoutine;
+	struct elem a;
+	
+	currentRoutine = ctx->routines + ctx->routine_current;
+	if (currentRoutine->top < 1) {
+		currentRoutine->panic = -1;
+		return;
+	}
+	a.type = INK_INTEGER;
+	a.value = currentRoutine->stack[currentRoutine->top - 1].type == INK_INTEGER;
+	ink_pop(ctx);
+	
+	ink_push(ctx, a);
+}
+
 static void print_array_of_codepoints(struct context* ctx) {
 	int tid, i;
 	struct ink_routine *currentRoutine;
@@ -1834,6 +1869,7 @@ int ink_std_library(struct context* ctx) {
 	v += ink_add_native(ctx, "pluck", pluck_elem);
 	v += ink_add_native(ctx, "return_if", return_if);
 	v += ink_add_native(ctx, "jump_if", jump_if);
+	v += ink_add_native(ctx, "is.int", is_int);
 #ifndef NOEXTRAARITHMETIC
 	v += ink_add_native(ctx, ">", gt_int);
 	v += ink_add_native(ctx, ">=", gte_int);
@@ -1851,6 +1887,7 @@ int ink_std_library(struct context* ctx) {
 	v += ink_add_native(ctx, "array.set", set_array);
 	v += ink_add_native(ctx, "array.size", get_size_array);
 	v += ink_add_native(ctx, "array.print_utf8", print_array_of_codepoints);
+	v += ink_add_native(ctx, "is.array", is_array);
 	v += ink_add_native(ctx, "stack.to_array", arrayify_stack);
 #endif // NOARRAYLIB