- Introduction
- Features
- Requirements
- Documentation
- Live Testing
- Template Example
- JSON Example
- Tests
- License
Qentem Engine is a self-contained lightweight library for rendering templates, designed to work in the back-end or the font-end, and because it has no specific requirements and is easy to use, it can be easily included in C++/C projects or even Java. There are modules made for PHP, Python, and Javascript, in case rendering templates in C++ is not the norm. The library has a fast JSON parser and its own logic and arithmetic evaluator for evaluating if, or calculating long algorithms. Also, it can be compiled to WASM, and tested directly in the browser, with all of its features like nested loops, nested if conditions, inline if, and variable replacement with auto-escape for HTML special characters.
-
General
- Cross-platform, header-only and self-contained; no external libraries are needed (including STL).
- Fast string to number and number to string (does not use CPU FPU).
- Supports 32-bit and 64-bit architectures, little and big-endian.
- No exceptions (try-catch and throw).
- Supports UTF-8, UTF-16 and UTF-32.
- Low memory usage.
-
Template engine
- Fast template rendering.
- Safe evaluation.
- Variable replacement with HTML auto-escape (optional: on by default).
- Raw variable replacement without HTML auto-escape.
- Nested loops (with data grouping and sorting).
- Nested if conditions.
- Inline if.
- Math tag.
-
JSON
- Fast parser.
- Fast stringify.
- Data grouping.
- Data sorting.
C++ 11+ compiler.
Note: iostream is used in tests at the moment.
Usage and examples @ Documentation.
Templates can be tested live @ JQen Tool.
#include "JSON.hpp"
#include "Template.hpp"
#include <iostream>
using Qentem::StringStream;
using Qentem::Template;
using Qentem::Value;
using Qentem::JSON;
int main() {
Value<char> value = JSON::Parse(R"(
[
{
"major": "Computer Science",
"students": [
{ "Name": "Student1", "GPA": 3.2 },
{ "Name": "Student2", "GPA": 3.8 },
{ "Name": "Student3", "GPA": 2.8 }
]
},
{
"major": "Math",
"students": [
{ "Name": "Student4", "GPA": 3.0 },
{ "Name": "Student5", "GPA": 2.5 },
{ "Name": "Student6", "GPA": 2.4 }
]
}
]
)");
const char *content = R"(
<html>
<body>
<div>
<h2>Students' list:</h2>
<loop value="department_val">
<h3>Major: {var:department_val[major]}</h3>
<ul>
<loop set="department_val[students]" value="student_val">
<li>
<span>Name: {var:student_val[Name]}</span>
<span>
GPA: {var:student_val[GPA]}
<if case="{var:student_val[GPA]} < 2.5"> (Inform adviser!)
<else if case="{var:student_val[GPA]} >= 3.5"> (President's List!)
<else if case="{var:student_val[GPA]} >= 3.0"> (Dean's List!)
</if>
</span>
</li>
</loop>
</ul>
</loop>
</div>
</body>
</html>
)";
StringStream<char> stream;
Template::Render(content, value, stream);
std::cout << stream << '\n';
}Note: the template does not have to be HTML.
#include "JSON.hpp"
#include <iostream>
using Value = Qentem::Value<char>;
using Qentem::JSON;
int main() {
Value abc = JSON::Parse(R"(["A","B","C"])");
Value v_arr; // To be used as an array.
v_arr += 0;
v_arr[1] = 10;
v_arr += nullptr;
v_arr += true;
v_arr += false;
v_arr[0] = "text"; // Overwrite
v_arr += abc; // Add sub-array as it is.
// Unpack all the values and merge them into v_arr.
v_arr.Merge(JSON::Parse(R"([100,200,300])"));
std::cout << v_arr.Stringify() << '\n';
/* Output:
[
"text",
10,
null,
true,
false,
[
"A",
"B",
"C"
],
100,
200,
300
]
*/
///////////////////////////////////////////
Value v_obj; // To be used as an object.
v_obj["key0"] = 0;
v_obj["key1"] = 10;
v_obj["key2"] = nullptr;
v_obj["key3"] = true;
v_obj["key4"] = false;
v_obj["key5"] = nullptr;
v_obj["key6"] = abc; // Add sub-array
// Replace any value with the same key, or add it if it does not exist.
v_obj += JSON::Parse(R"({"key0": "text", "key4": true, "key5": 500, "key7": [1,2,3,4], "key8": null})");
std::cout << v_obj.Stringify() << '\n';
/* Output:
{
"key0": "text",
"key1": 10,
"key2": null,
"key3": true,
"key4": true,
"key5": 500,
"key6": [
"A",
"B",
"C"
],
"key7": [
1,
2,
3,
4
],
"key8": null
}
*/
///////////////////////////////////////////
// Sorting
v_arr.Reset();
v_arr += 4;
v_arr += 1;
v_arr += 3;
v_arr += 5;
v_arr += 2;
v_arr += 7;
v_arr += 6;
v_arr.Sort(); // Ascending
std::cout << v_arr.Stringify() << '\n';
// Output: [1,2,3,4,5,6,7]
v_arr.Sort(false); // Descending
std::cout << v_arr.Stringify() << '\n';
// Output: [7,6,5,4,3,2,1]
///////////////////////////////////////////
// Grouping
v_arr = JSON::Parse(
R"([
{"year":2019,"month":4},
{"year":2020,"month":5},
{"year":2017,"month":1},
{"year":2020,"month":6},
{"year":2018,"month":2},
{"year":2020,"month":7},
{"year":2018,"month":3}])");
Value v_arr2;
if (v_arr.GroupBy(v_arr2, "year")) {
v_arr2.Sort();
std::cout << v_arr2.Stringify() << '\n';
}
/* Output:
{
"2017": [
{
"month": 1
}
],
"2018": [
{
"month": 2
},
{
"month": 3
}
],
"2019": [
{
"month": 4
}
],
"2020": [
{
"month": 5
},
{
"month": 6
},
{
"month": 7
}
]
}
*/
}There are over 23k lines of code for testing; 5 times the library. To run the tests that take less than 0.01s to finish:
-
gcc/clang
mkdir Build c++ -I ./Include ./Tests/Test.cpp -o ./Build/QTest.bin ./Build/QTest.bin
-
cmake
mkdir Build cd Build cmake .. cmake --build . ctest -C Debug
MIT License
Copyright (c) 2024 Hani Ammar
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.