Tests Reference

Tests are boolean predicates used withisin conditionals.

Usage

{% if value is test %}
{% if value is test(arg) %}
{% if value is not test %}

Type Tests

defined

Value is not None.

{% if user is defined %}
    {{ user.name }}
{% end %}

undefined

Value is None.

{% if user is undefined %}
    <p>Not logged in</p>
{% end %}

none

Value is None (alias for undefined).

{% if value is none %}

string

Value is a string.

{% if value is string %}
    {{ value | upper }}
{% end %}

number

Value is int or float (not bool).

{% if value is number %}
    {{ value * 2 }}
{% end %}

sequence

Value is list, tuple, or string.

{% if items is sequence %}
    {{ items | length }} items
{% end %}

mapping

Value is a dict.

{% if data is mapping %}
    {{ data.keys() | list }}
{% end %}

iterable

Value supports iteration.

{% if items is iterable %}
    {% for item in items %}...{% end %}
{% end %}

callable

Value is callable.

{% if func is callable %}
    {{ func() }}
{% end %}

Boolean Tests

true

Value is exactly True.

{% if flag is true %}
    Enabled
{% end %}

false

Value is exactly False.

{% if flag is false %}
    Disabled
{% end %}

Number Tests

odd

Integer is odd.

{% if loop.index is odd %}
    <tr class="odd">
{% end %}

even

Integer is even.

{% if loop.index is even %}
    <tr class="even">
{% end %}

divisibleby

Integer is divisible by N.

{% if count is divisibleby(3) %}
    Multiple of 3
{% end %}

Comparison Tests

eq / equalto

Equal to value.

{% if status is eq("active") %}
{% if count is equalto(0) %}

ne

Not equal to value.

{% if status is ne("deleted") %}

lt / lessthan

Less than value.

{% if count is lt(10) %}
{% if age is lessthan(18) %}

le

Less than or equal.

{% if score is le(100) %}

gt / greaterthan

Greater than value.

{% if count is gt(0) %}
{% if age is greaterthan(21) %}

ge

Greater than or equal.

{% if level is ge(5) %}

sameas

Identity comparison (is).

{% if a is sameas(b) %}
    Same object
{% end %}

in

Value is in sequence.

{% if role is in(["admin", "moderator"]) %}
    Has permissions
{% end %}

String Tests

lower

String is all lowercase.

{% if text is lower %}
    Already lowercase
{% end %}

upper

String is all uppercase.

{% if text is upper %}
    Already uppercase
{% end %}

match

String matches regex pattern.

{% if email is match(".*@.*\\..*") %}
    Valid email format
{% end %}

Negation

Useis notto negate any test:

{% if value is not defined %}
{% if count is not even %}
{% if user is not none %}
{% if status is not eq("active") %}

Examples

Type Checking

{% if data is mapping %}
    {% for key, value in data.items() %}
        {{ key }}: {{ value }}
    {% end %}
{% elif data is sequence %}
    {% for item in data %}
        {{ item }}
    {% end %}
{% elif data is string %}
    {{ data }}
{% end %}

Loop Styling

<table>
{% for row in data %}
    <tr class="{% if loop.index is odd %}odd{% else %}even{% end %}">
        <td>{{ row.name }}</td>
    </tr>
{% end %}
</table>

Permission Checks

{% if user is defined %}
    {% if user.role is in(["admin", "moderator"]) %}
        {% include "admin-toolbar.html" %}
    {% end %}
{% end %}

Pagination

{% if page is gt(1) %}
    <a href="?page={{ page - 1 }}">Previous</a>
{% end %}

{% if page is lt(total_pages) %}
    <a href="?page={{ page + 1 }}">Next</a>
{% end %}