README

Simple yet powerful Jinja-like templating system for HTML written in PHP.

See: https://www.tqdev.com/2026-jinja-templating-engine-html-php/

Overview

MintyPHP's Template engine provides a simple yet powerful Jinja-like templating system with variable interpolation, control structures, filters, and expression evaluation. Templates are HTML-safe by default with automatic escaping.

Requirements

• PHP 8+

Installation

Add a dependency with Composer:

composer require mintyphp/template

Usage

use MintyPHP\Template\Template;

$template = new Template();
echo $template->render('<p>{{hi}}</p>',['hi' => 'Hello world']);
// Outputs: <p>Hello world</p>

BNF Syntax

<template>        ::= <content>*

<content>         ::= <literal> | <variable> | <control> | <comment>

<literal>         ::= any text not matching other patterns

<variable>        ::= "{{" <ws>? <expression> <filter-chain>? <ws>? "}}"

<control>         ::= <if-block> | <for-block> | <block> | <extends> | <include>

<comment>         ::= "{#" <any-text> "#}"

<extends>         ::= "{%" <ws>? "extends" <ws> <string> <ws>? "%}"

<include>         ::= "{%" <ws>? "include" <ws> <string> <ws>? "%}"

<block>           ::= <block-tag> <content>* <endblock-tag>

<block-tag>       ::= "{%" <ws>? "block" <ws> <identifier> <ws>? "%}"

<endblock-tag>    ::= "{%" <ws>? "endblock" <ws>? "%}"

<if-block>        ::= <if-tag> <content>* <elseif-tag>* <else-tag>? <endif-tag>

<if-tag>          ::= "{%" <ws>? "if" <ws> <expression> <filter-chain>? <ws>? "%}"

<elseif-tag>      ::= "{%" <ws>? "elseif" <ws> <expression> <filter-chain>? <ws>? "%}" <content>*

<else-tag>        ::= "{%" <ws>? "else" <ws>? "%}" <content>*

<endif-tag>       ::= "{%" <ws>? "endif" <ws>? "%}"

<for-block>       ::= <for-tag> <content>* <endfor-tag>

<for-tag>         ::= "{%" <ws>? "for" <ws> <for-vars> <ws> "in" <ws> <expression> <filter-chain>? <ws>? "%}"

<for-vars>        ::= <identifier> | <identifier> <ws>? "," <ws>? <identifier>

<endfor-tag>      ::= "{%" <ws>? "endfor" <ws>? "%}"

<expression>      ::= <logical-or>

<logical-or>      ::= <logical-and> (("or" | "||") <logical-and>)*

<logical-and>     ::= <test-expr> (("and" | "&&") <test-expr>)*

<test-expr>       ::= <equality> (("is" "not"?) <test>)?

<test>            ::= <identifier> ("(" <filter-args> ")")?

<equality>        ::= <comparison> (("==" | "!=") <comparison>)*

<comparison>      ::= <additive> (("<" | ">" | "<=" | ">=") <additive>)*

<additive>        ::= <multiplicative> (("+" | "-") <multiplicative>)*

<multiplicative>  ::= <unary> (("*" | "/" | "%") <unary>)*

<unary>           ::= "not" <unary> | <primary>

<primary>         ::= <number> | <string> | <path> | "(" <expression> ")"

<filter-chain>    ::= ("|" <filter>)+

<filter>          ::= <identifier> ("(" <filter-args> ")")?

<filter-args>     ::= <filter-arg> ("," <ws>? <filter-arg>)*

<filter-arg>      ::= <string> | <number> | <path>

<path>            ::= <identifier> ("." <identifier>)*

<identifier>      ::= [a-zA-Z_][a-zA-Z0-9_]*

<number>          ::= [0-9]+ ("." [0-9]+)?

<string>          ::= '"' (<char> | <escape-seq>)* '"'

<escape-seq>      ::= "\\" <any-char>

<ws>              ::= [ \t\n\r]+

Operators

Arithmetic Operators

• + Addition (also string concatenation)
• - Subtraction
• * Multiplication
• / Division
• % Modulo

Comparison Operators

• == Equal
• != Not equal
• < Less than
• > Greater than
• <= Less than or equal
• >= Greater than or equal

Logical Operators

• and, && Logical AND
• or, || Logical OR
• not Logical NOT (unary)

Operator Precedence (highest to lowest)

1. not (unary)
2. *, /, %
3. +, -
4. <, >, <=, >=
5. ==, !=
6. and, &&
7. or, ||

Features

• Variable interpolation with {{ }} syntax
• Control structures with {% %} syntax (if/elseif/else, for loops)
• Template inheritance with {% extends %} and {% block %}
• Template inclusion with {% include %}
• Comments with {# #} syntax
• Expression evaluation with full operator support
• Filters with pipe syntax |
• Builtin filters for common transformations
• Tests with is keyword for value checking
• Nested data access with dot notation
• HTML escaping by default
• Raw output with raw filter
• Custom filters and tests

Examples

Example 1: Basic Variable Interpolation

Data (JSON):

{
    "title": "Welcome",
    "username": "Alice",
    "message": "Hello, World!"
}

Template:

<!DOCTYPE html>
<html>
    <head>
        <title>{{ title }}</title>
    </head>
    <body>
        <h1>{{ message }}</h1>
        <p>Logged in as: {{ username }}</p>
    </body>
</html>

Output:

<!DOCTYPE html>
<html>
    <head>
        <title>Welcome</title>
    </head>
    <body>
        <h1>Hello, World!</h1>
        <p>Logged in as: Alice</p>
    </body>
</html>

Example 2: HTML Escaping

Data (JSON):

{
    "user_input": "<script>alert('XSS')</script>",
    "safe_html": "<strong>Bold Text</strong>"
}

Template:

<div>
    <p>User input (escaped): {{ user_input }}</p>
    <p>Raw HTML: {{ safe_html|raw }}</p>
</div>

Output:

<div>
    <p>
        User input (escaped):
        &lt;script&gt;alert(&#039;XSS&#039;)&lt;/script&gt;
    </p>
    <p>Raw HTML: <strong>Bold Text</strong></p>
</div>

Example 3: Conditional Rendering

Data (JSON):

{
    "user": {
        "name": "Bob",
        "is_admin": true,
        "age": 25
    }
}

Template:

<div class="user-profile">
    <h2>{{ user.name }}</h2>

    {% if user.is_admin %}
    <span class="badge">Administrator</span>
    {% endif %}

    {% if user.age >= 18 %}
    <p>Adult user ({{ user.age }} years old)</p>
    {% else %}
    <p>Minor user ({{ user.age }} years old)</p>
    {% endif %}
</div>

Output:

<div class="user-profile">
    <h2>Bob</h2>

    <span class="badge">Administrator</span>
    
    <p>Adult user (25 years old)</p>
</div>

Example 4: If-ElseIf-Else Chain

Data (JSON):

{
    "score": 85
}

Template:

<div class="grade">
    {% if score >= 90 %}
    <span class="A">Grade: A - Excellent!</span>
    {% elseif score >= 80 %}
    <span class="B">Grade: B - Good Job!</span>
    {% elseif score >= 70 %}
    <span class="C">Grade: C - Fair</span>
    {% elseif score >= 60 %}
    <span class="D">Grade: D - Needs Improvement</span>
    {% else %}
    <span class="F">Grade: F - Failed</span>
    {% endif %}
</div>

Output:

<div class="grade">
    <span class="B">Grade: B - Good Job!</span>
</div>

Example 5: For Loops with Arrays

Data (JSON):

{
    "fruits": ["Apple", "Banana", "Cherry", "Date"]
}

Template:

<ul class="fruit-list">
    {% for fruit in fruits %}
    <li>{{ fruit }}</li>
    {% endfor %}
</ul>

Output:

<ul class="fruit-list">
    <li>Apple</li>
    <li>Banana</li>
    <li>Cherry</li>
    <li>Date</li>
</ul>

Example 6: For Loops with Key-Value Pairs

Data (JSON):

{
    "products": {
        "laptop": "999.99",
        "mouse": "29.99",
        "keyboard": "79.99"
    }
}

Template:

<table>
    <thead>
        <tr>
            <th>Product</th>
            <th>Price</th>
        </tr>
    </thead>
    <tbody>
        {% for product, price in products %}
        <tr>
            <td>{{ product }}</td>
            <td>${{ price }}</td>
        </tr>
        {% endfor %}
    </tbody>
</table>

Output:

<table>
    <thead>
        <tr>
            <th>Product</th>
            <th>Price</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>laptop</td>
            <td>$999.99</td>
        </tr>
        <tr>
            <td>mouse</td>
            <td>$29.99</td>
        </tr>
        <tr>
            <td>keyboard</td>
            <td>$79.99</td>
        </tr>
    </tbody>
</table>

Example 7: Nested For Loops

Data (JSON):

{
    "grid": [
        [1, 2, 3],
        [4, 5, 6],
        [7, 8, 9]
    ]
}

Template:

<table class="grid">
    {% for row in grid %}
    <tr>
        {% for cell in row %}
        <td>{{ cell }}</td>
        {% endfor %}
    </tr>
    {% endfor %}
</table>

Output:

<table class="grid">
    <tr>
        <td>1</td>
        <td>2</td>
        <td>3</td>
    </tr>
    <tr>
        <td>4</td>
        <td>5</td>
        <td>6</td>
    </tr>
    <tr>
        <td>7</td>
        <td>8</td>
        <td>9</td>
    </tr>
</table>

Example 8: Nested Data Access

Data (JSON):

{
    "company": {
        "name": "Tech Corp",
        "employees": [
            {
                "name": "Alice",
                "position": "Developer",
                "salary": 80000
            },
            {
                "name": "Bob",
                "position": "Designer",
                "salary": 75000
            }
        ]
    }
}

Template:

<div class="company">
    <h1>{{ company.name }}</h1>
    <h2>Employees</h2>
    <ul>
        {% for employee in company.employees %}
        <li>
            <strong>{{ employee.name }}</strong> - {{ 
                employee.position }} (${{ employee.salary }})
        </li>
        {% endfor %}
    </ul>
</div>

Output:

<div class="company">
    <h1>Tech Corp</h1>
    <h2>Employees</h2>
    <ul>
        <li>
            <strong>Alice</strong> - Developer ($80000)
        </li>
        <li>
            <strong>Bob</strong> - Designer ($75000)
        </li>
    </ul>
</div>

Example 9: Expressions in Variables

Data (JSON):

{
    "price": 100,
    "quantity": 3,
    "tax_rate": 0.08
}

Template:

<div class="invoice">
    <p>Price per item: ${{ price }}</p>
    <p>Quantity: {{ quantity }}</p>
    <p>Subtotal: ${{ price * quantity }}</p>
    <p>Tax (8%): ${{ price * quantity * tax_rate }}</p>
    <p>Total: ${{ price * quantity * (1 + tax_rate) }}</p>
</div>

Output:

<div class="invoice">
    <p>Price per item: $100</p>
    <p>Quantity: 3</p>
    <p>Subtotal: $300</p>
    <p>Tax (8%): $24</p>
    <p>Total: $324</p>
</div>

Example 10: String Concatenation

Data (JSON):

{
    "first_name": "John",
    "last_name": "Doe",
    "title": "Dr."
}

Template:

<div class="profile">
    <h2>{{ title + " " + first_name + " " + last_name }}</h2>
    <p>Full name: {{ first_name + " " + last_name }}</p>
</div>

Output:

<div class="profile">
    <h2>Dr. John Doe</h2>
    <p>Full name: John Doe</p>
</div>

Example 11: Complex Conditions

Data (JSON):

{
    "user": {
        "age": 25,
        "is_premium": true,
        "credits": 150
    }
}

Template:

<div class="access">
    {% if user.age >= 18 && user.is_premium %}
    <p>✓ Full access granted</p>
    {% endif %}
    {% if user.credits > 100 || user.is_premium %}
    <p>✓ Can download premium content</p>
    {% endif %}
    {% if (user.age >= 21 && user.credits > 50) || user.is_premium %}
    <p>✓ Can access exclusive features</p>
    {% endif %}
</div>

Output:

<div class="access">
    <p>✓ Full access granted</p>
    <p>✓ Can download premium content</p>
    <p>✓ Can access exclusive features</p>
</div>

Example 12: For Loop with Conditionals

Data (JSON):

{
    "orders": [
        { "id": 1001, "status": "shipped", "total": 99.99 },
        { "id": 1002, "status": "pending", "total": 149.99 },
        { "id": 1003, "status": "delivered", "total": 79.99 },
        { "id": 1004, "status": "cancelled", "total": 199.99 }
    ]
}

Template:

<table class="orders">
    <tr>
        <th>Order ID</th>
        <th>Total</th>
        <th>Status</th>
    </tr>
    {% for order in orders %}
    <tr class="{% if order.status == 'cancelled' %}cancelled{% elseif order.status == 'delivered' %}success{% endif %}">
        <td>#{{ order.id }}</td>
        <td>${{ order.total }}</td>
        <td>
            {% if order.status == "shipped" %}
            🚚 Shipped
            {% elseif order.status == "pending" %}
            ⏳ Pending
            {% elseif order.status == "delivered" %}
            ✓ Delivered
            {% else %}
            ✗ Cancelled
            {% endif %}
        </td>
    </tr>
    {% endfor %}
</table>

Output:

<table class="orders">
    <tr>
        <th>Order ID</th>
        <th>Total</th>
        <th>Status</th>
    </tr>
    <tr class="">
        <td>#1001</td>
        <td>$99.99</td>
        <td>
            🚚 Shipped
        </td>
    </tr>
    <tr class="">
        <td>#1002</td>
        <td>$149.99</td>
        <td>
            ⏳ Pending
        </td>
    </tr>
    <tr class="success">
        <td>#1003</td>
        <td>$79.99</td>
        <td>
            ✓ Delivered
        </td>
    </tr>
    <tr class="cancelled">
        <td>#1004</td>
        <td>$199.99</td>
        <td>
            ✗ Cancelled
        </td>
    </tr>
</table>

Example 13: Comments

Data (JSON):

{
    "username": "Alice",
    "email": "alice@example.com"
}

Template:

<div class="user">
    {# This is a comment and won't appear in output #}
    <h2>{{ username }}</h2>

    {# Multi-line comment 
    These can span multiple lines and 
    won't be rendered #}
    <p>Email: {{ email }}</p>
    {# TODO: Add phone number field #}
</div>

Output:

<div class="user">
    <h2>Alice</h2>

    <p>Email: alice@example.com</p>
</div>

Example 14: Blog Post List

Data (JSON):

{
    "blog": {
        "title": "My Tech Blog",
        "posts": [
            {
                "id": 1,
                "title": "Getting Started with PHP",
                "author": "Alice",
                "date": "2024-01-15",
                "excerpt": "Learn the basics of PHP programming...",
                "published": true,
                "views": 1234
            },
            {
                "id": 2,
                "title": "Advanced Template Engines",
                "author": "Bob",
                "date": "2024-01-20",
                "excerpt": "Deep dive into template engine design...",
                "published": true,
                "views": 856
            },
            {
                "id": 3,
                "title": "Upcoming Features",
                "author": "Alice",
                "date": "2024-02-01",
                "excerpt": "What's coming next...",
                "published": false,
                "views": 0
            }
        ]
    }
}

Template:

<!DOCTYPE html>
<html>
    <head>
        <title>{{ blog.title }}</title>
    </head>
    <body>
        <header>
            <h1>{{ blog.title }}</h1>
        </header>

        <main>
            {% for post in blog.posts %} {% if post.published %}
            <article class="post">
                <h2>{{ post.title }}</h2>
                <div class="meta">
                    By {{ post.author }} on {{ post.date }}
                    {% if post.views > 1000 %}
                    <span class="popular">🔥 Popular</span>
                    {% endif %}
                </div>
                <p>{{ post.excerpt }}</p>
                <a href="/post/{{ post.id }}">Read more...</a>
            </article>
            {% endif %} {% endfor %}
        </main>
    </body>
</html>

Output:

<!DOCTYPE html>
<html>
    <head>
        <title>My Tech Blog</title>
    </head>
    <body>
        <header>
            <h1>My Tech Blog</h1>
        </header>

        <main>
            <article class="post">
                <h2>Getting Started with PHP</h2>
                <div class="meta">
                    By Alice on 2024-01-15
                    <span class="popular">🔥 Popular</span>
                </div>
                <p>Learn the basics of PHP programming...</p>
                <a href="/post/1">Read more...</a>
            </article>
            <article class="post">
                <h2>Advanced Template Engines</h2>
                <div class="meta">
                    By Bob on 2024-01-20
                </div>
                <p>Deep dive into template engine design...</p>
                <a href="/post/2">Read more...</a>
            </article>
        </main>
    </body>
</html>

Example 15: Dashboard with Statistics

Data (JSON):

{
    "dashboard": {
        "user": "Admin",
        "stats": {
            "total_users": 1523,
            "active_users": 892,
            "total_revenue": 45678.90,
            "pending_orders": 23
        },
        "recent_activities": [
            {
                "user": "Alice",
                "action": "registered",
                "time": "2 minutes ago"
            },
            {
                "user": "Bob",
                "action": "made a purchase",
                "time": "5 minutes ago"
            },
            {
                "user": "Charlie",
                "action": "updated profile",
                "time": "10 minutes ago"
            }
        ]
    }
}

Template:

<!DOCTYPE html>
<html>
    <head>
        <title>Admin Dashboard</title>
    </head>
    <body>
        <h1>Welcome, {{ dashboard.user }}</h1>

        <div class="stats-grid">
            <div class="stat-card">
                <h3>Total Users</h3>
                <p class="number">{{ dashboard.stats.total_users }}</p>
            </div>

            <div class="stat-card">
                <h3>Active Users</h3>
                <p class="number">{{ dashboard.stats.active_users }}</p>
                <small>{{ dashboard.stats.active_users * 100 /
                    dashboard.stats.total_users }}% active</small>
            </div>

            <div class="stat-card {% if dashboard.stats.total_revenue > 40000 %}success{% endif %}">
                <h3>Revenue</h3>
                <p class="number">${{ dashboard.stats.total_revenue }}</p>
            </div>

            <div class="stat-card {% if dashboard.stats.pending_orders > 20 %}warning{% endif %}">
                <h3>Pending Orders</h3>
                <p class="number">{{ dashboard.stats.pending_orders }}</p>
            </div>
        </div>

        <div class="recent-activity">
            <h2>Recent Activity</h2>
            <ul>
                {% for activity in dashboard.recent_activities %}
                <li>
                    <strong>{{ activity.user }}</strong> {{ activity.action }}
                    <span class="time">{{ activity.time }}</span>
                </li>
                {% endfor %}
            </ul>
        </div>
    </body>
</html>

Output:

<!DOCTYPE html>
<html>
    <head>
        <title>Admin Dashboard</title>
    </head>
    <body>
        <h1>Welcome, Admin</h1>

        <div class="stats-grid">
            <div class="stat-card">
                <h3>Total Users</h3>
                <p class="number">1523</p>
            </div>

            <div class="stat-card">
                <h3>Active Users</h3>
                <p class="number">892</p>
                <small>58.568611293499% active</small>
            </div>

            <div class="stat-card success">
                <h3>Revenue</h3>
                <p class="number">$45678.9</p>
            </div>

            <div class="stat-card warning">
                <h3>Pending Orders</h3>
                <p class="number">23</p>
            </div>
        </div>

        <div class="recent-activity">
            <h2>Recent Activity</h2>
            <ul>
                <li>
                    <strong>Alice</strong> registered
                    <span class="time">2 minutes ago</span>
                </li>
                <li>
                    <strong>Bob</strong> made a purchase
                    <span class="time">5 minutes ago</span>
                </li>
                <li>
                    <strong>Charlie</strong> updated profile
                    <span class="time">10 minutes ago</span>
                </li>
            </ul>
        </div>
    </body>
</html>

Template Inheritance

MintyPHP's template engine supports template inheritance through {% extends %} and {% block %} directives, allowing you to create reusable base templates.

Example: Base Template

base.html:

<!DOCTYPE html>
<html>
    <head>
        <title>{% block title %}Default Title{% endblock %}</title>
        {% block head %}{% endblock %}
    </head>
    <body>
        <header>
            <h1>My Website</h1>
        </header>
        <main>
            {% block content %}
            <p>Default content</p>
            {% endblock %}
        </main>
        <footer>
            <p>&copy; 2026 My Website</p>
        </footer>
    </body>
</html>

Example: Child Template

page.html:

{% extends "base.html" %}

{% block title %}Welcome Page{% endblock %}

{% block head %}
<style>
    .highlight { color: blue; }
</style>
{% endblock %}

{% block content %}
<h2>Welcome!</h2>
<p class="highlight">This replaces the default content.</p>
{% endblock %}

Notes:

• {% extends %} must be the first non-whitespace element in the child template
• Blocks defined in the child completely replace blocks in the parent
• Blocks not overridden use the parent's default content
• Template inheritance requires a template loader function

Template Inclusion

Use {% include %} to insert another template at a specific point.

Example: Including Templates

header.html:

<header>
    <h1>{{ site_name }}</h1>
</header>

main.html:

{% include "header.html" %}
<main>
    <p>{{ content }}</p>
</main>

Notes:

• Included templates share the same data context as the parent
• Requires a template loader function to be configured

Builtin Filters

MintyPHP includes comprehensive builtin filters for common transformations.

String Filters

lower

Convert to lowercase.

{{ "HELLO"|lower }} = hello

upper

Convert to uppercase.

{{ "hello"|upper }} = HELLO

capitalize

Capitalize first character.

{{ "hello world"|capitalize }} = Hello world

title

Title case (capitalize each word).

{{ "hello world"|title }} = Hello World

trim

Remove leading/trailing whitespace.

{{ "  hello  "|trim }} = hello

truncate(length, end)

Truncate string to length (default 255, default end "...") without breaking words.

{{ "Hello World"|truncate(8) }} = Hello...
{{ "Hello World"|truncate(10, "..") }} = Hello..

replace(old, new, count)

Replace substring occurrences.

{{ "Hello World"|replace("Hello", "Goodbye") }} = Goodbye World
{{ "aaaaargh"|replace("a", "d'oh, ", 2) }} = d'oh, d'oh, aaargh

split(separator)

Split string into array.

{{ "1,2,3"|split(",")|join("|") }} = 1|2|3
{{ "123"|split()|join("|") }} = 1|2|3

urlencode

URL-encode a string.

{{ "hello world"|urlencode }} = hello+world

reverse

Reverse string or array.

{{ "hello"|reverse }} = olleh
{{ [1,2,3]|reverse|join(",") }} = 3,2,1

Numeric Filters

abs

Absolute value.

{{ -42|abs }} = 42

round(precision, method)

Round number (default precision=0, method="common"). Available methods: common, ceil, floor, down, even/banker, odd, awayzero, tozero.

{{ 42.55|round }} = 43
{{ 42.55|round(1, "floor") }} = 42.5
{{ 2.5|round(0, "even") }} = 2

sprintf(format)

Format with sprintf.

{{ 3.14159|sprintf("%.2f") }} = 3.14
{{ 42|sprintf("%05d") }} = 00042

filesizeformat(binary)

Format bytes as human-readable size.

{{ 13000|filesizeformat }} = 13.0 kB
{{ 1024|filesizeformat(true) }} = 1.0 KiB
{{ 1500000|filesizeformat }} = 1.5 MB

Array/Collection Filters

length / count

Get count of items or string length.

{{ [1,2,3]|length }} = 3
{{ "hello"|length }} = 5

first(n)

Get first item or first n items.

{{ [1,2,3,4]|first }} = 1
{{ [1,2,3,4]|first(2) }} = [1,2]

last(n)

Get last item or last n items.

{{ [1,2,3,4]|last }} = 4
{{ [1,2,3,4]|last(2) }} = [3,4]

join(separator, attribute)

Join array elements with separator.

{{ [1,2,3]|join("|") }} = 1|2|3
{{ users|join(", ", "username") }} = alice, bob, charlie

sum(attribute)

Sum numeric values in array.

{{ [1,2,3]|sum }} = 6
{{ items|sum("price") }} = 150.50

Utility Filters

default(value, boolean)

Return default if value is null (or falsy with boolean=true).

{{ missing_var|default("N/A") }} = N/A
{{ ""|default("empty", true) }} = empty
{{ 0|default("zero", true) }} = zero

attr(name)

Get attribute by name.

{{ user|attr("email") }} = user@example.com

debug / d

Pretty-print value as JSON for debugging.

{{ user|debug }} = <pre>{"name":"Alice","email":"alice@example.com"}</pre>

raw

Output unescaped HTML (builtin).

{{ "<strong>Bold</strong>"|raw }} = <strong>Bold</strong>

Builtin Tests

Tests allow you to check properties of values using the is keyword in expressions.

Syntax

{% if variable is testname %}
{% if variable is not testname %}
{% if variable is testname(arg) %}

Available Tests

defined

Check if variable is defined.

{% if user is defined %}
    User exists: {{ user }}
{% endif %}

undefined

Check if variable is undefined.

{% if missing is undefined %}
    Variable not defined
{% endif %}

null

Check if value is null.

{% if value is null %}
    Value is null
{% endif %}

even

Check if number is even.

{% if count is even %}
    Count is even
{% endif %}

odd

Check if number is odd.

{% if count is odd %}
    Count is odd
{% endif %}

divisibleby(n)

Check if number is divisible by n.

{% if total is divisibleby(3) %}
    Divisible by 3
{% endif %}

number

Check if value is numeric.

{% if value is number %}
    {{ value }} is a number
{% endif %}

string

Check if value is a string.

{% if name is string %}
    {{ name }} is a string
{% endif %}

iterable

Check if value can be iterated.

{% if items is iterable %}
    {% for item in items %}
        {{ item }}
    {% endfor %}
{% endif %}

Test Negation

Use is not to negate tests:

{% if value is not null %}
    Value exists
{% endif %}

Custom Filters

Custom filters can be provided to the Template constructor.

PHP Usage Example:

$data = ['name' => 'john doe', 'date' => 'May 13, 1980'];

$filters = [
    'upper' => 'strtoupper',
    'capitalize' => 'ucfirst',
    'dateFormat' => fn($date, $format) => date($format, strtotime($date))
];

$template = new Template(null, $filters);
$html = $template->render(
    'Hello {{ name|upper }}, date: {{ date|dateFormat("Y-m-d") }}',
    $data
);
// Output: Hello JOHN DOE, date: 1980-05-13

Custom Tests

Custom tests can be provided as the third argument to the Template constructor.

PHP Usage Example:

$data = ['age' => 21];

$tests = [
    'adult' => fn($age) => is_numeric($age) && $age >= 18
];

$template = new Template(null, null, $tests);
$html = $template->render(
    '{% if age is adult %}You are an adult{% else %}You are a minor{% endif %}',
    $data
);
// Output: Adult

Notes

• All output is HTML-escaped by default for security
• Use the raw filter to output unescaped HTML: {{ content|raw }}
• Whitespace in templates is generally preserved
• Lines containing only whitespace and a {% %} tag or {# #} comment are removed
• Expressions support parentheses for grouping: {{ (a + b) * c }}
• Paths use dot notation for nested access: {{ user.profile.name }}
• For loops can iterate with values only or with key-value pairs
• Comments are completely removed from output and don't affect whitespace
• Builtin filters are available automatically without configuration
• Tests use the is keyword: {% if value is defined %}

Template Inheritance Notes

• The {% extends %} directive must be the first non-whitespace element in a child template
• Template inheritance and {% include %} require a template loader function to be configured
• Child block content completely replaces parent block content
• Blocks not overridden in the child will use the parent's default content
• Blocks can be nested, and each can be independently overridden
• Variables, expressions, and all other template features work inside blocks

Configuration Example

// Configure template loader for extends/include support
$templateLoader = function(string $name): ?string {
    $path = __DIR__ . '/templates/' . $name;
    return file_exists($path) ? file_get_contents($path) : null;
};

$template = new Template($templateLoader);
$result = $template->render($templateContent, $data);