min, max functions

README.md

@@ -183,6 +183,10 @@ render("{{ odd(42) }}", data); // false
 render("{{ even(42) }}", data); // true
 render("{{ divisibleBy(42, 7) }}", data); // true
 
+// Maximum and minimum values from a list
+render("{{ max([1, 2, 3]) }}", data); // 3
+render("{{ min([-2.4, -1.2, 4.5]) }}", data); // -2.4
+
 // Set default values if variables are not defined
 render("Hello {{ default(neighbour, \"my friend\") }}!"); // "Hello Peter!"
 render("Hello {{ default(colleague, \"my friend\") }}!"); // "Hello my friend!"

src/inja.hpp

@@ -248,6 +248,8 @@ struct Parsed {
 		DivisibleBy,
 		Odd,
 		Even,
+		Max,
+		Min,
 		ReadJson,
 		Default,
 		Callback
@@ -396,6 +398,14 @@ public:
 				const int number = eval_expression<int>(element.args[0], data);
 				return (number % 2 == 0);
 			}
+			case Parsed::Function::Max: {
+				const std::vector<json> list = eval_expression<std::vector<json>>(element.args[0], data);
+				return *std::max_element(list.begin(), list.end());
+			}
+			case Parsed::Function::Min: {
+				const std::vector<json> list = eval_expression<std::vector<json>>(element.args[0], data);
+				return *std::min_element(list.begin(), list.end());
+			}
 			case Parsed::Function::Not: {
 				return not eval_expression<bool>(element.args[0], data);
 			}
@@ -601,6 +611,8 @@ public:
 		{Parsed::Function::DivisibleBy, function_regex("divisibleBy", 2)},
 		{Parsed::Function::Odd, function_regex("odd", 1)},
 		{Parsed::Function::Even, function_regex("even", 1)},
+		{Parsed::Function::Max, function_regex("max", 1)},
+		{Parsed::Function::Min, function_regex("min", 1)},
 		{Parsed::Function::ReadJson, Regex{"\\s*([^\\(\\)]*\\S)\\s*"}},
 		{Parsed::Function::Default, function_regex("default", 2)}
 	};

test/src/unit-renderer.cpp

@@ -142,6 +142,18 @@ TEST_CASE("functions") {
 		// CHECK_THROWS_WITH( env.render("{{ even(name) }}", data), "[json.exception.type_error.302] type must be number, but is string" );
 	}
 
+	SECTION("max") {
+		CHECK( env.render("{{ max([1, 2, 3]) }}", data) == "3" );
+		CHECK( env.render("{{ max([-5.2, 100.2, 2.4]) }}", data) == "100.2" );
+		// CHECK_THROWS_WITH( env.render("{{ even(name) }}", data), "[json.exception.type_error.302] type must be number, but is string" );
+	}
+
+	SECTION("min") {
+		CHECK( env.render("{{ min([1, 2, 3]) }}", data) == "1" );
+		CHECK( env.render("{{ min([-5.2, 100.2, 2.4]) }}", data) == "-5.2" );
+		// CHECK_THROWS_WITH( env.render("{{ even(name) }}", data), "[json.exception.type_error.302] type must be number, but is string" );
+	}
+
 	SECTION("default") {
 		CHECK( env.render("{{ default(11, 0) }}", data) == "11" );
 		CHECK( env.render("{{ default(nothing, 0) }}", data) == "0" );