Built-in Tests (28)

Tests check values using the is operator (Jinja2 syntax).

Usage

{% if value is defined %}...{% endif %}
{% if num is even %}...{% endif %}
{% if num is divisibleby(3) %}...{% endif %}

Negation

Use is not for negative tests:

{% if value is not none %}...{% endif %}
{% if num is not even %}...{% endif %}

Available Tests

Type Tests

Test	Description	Example
defined	Variable exists	{% if x is defined %}
undefined	Variable doesn’t exist	{% if x is undefined %}
none	Value is null/undefined	{% if x is none %}
boolean	Value is boolean	{% if x is boolean %}
string	Value is string	{% if x is string %}
number	Value is number	{% if x is number %}
integer	Value is integer	{% if x is integer %}
float	Value is float	{% if x is float %}
mapping	Value is object/dict	{% if x is mapping %}
iterable	Value is iterable	{% if x is iterable %}
sequence	Value is array	{% if x is sequence %}
callable	Value is function	{% if x is callable %}

Number Tests

Test	Description	Example
even	Number is even	{% if n is even %}
odd	Number is odd	{% if n is odd %}
divisibleby(n)	Divisible by n	{% if n is divisibleby(3) %}

Comparison Tests

Test	Description	Example
eq(value)	Equal to	{% if x is eq(5) %}
ne(value)	Not equal to	{% if x is ne(5) %}
lt(value)	Less than	{% if x is lt(10) %}
le(value)	Less than or equal	{% if x is le(10) %}
gt(value)	Greater than	{% if x is gt(0) %}
ge(value)	Greater than or equal	{% if x is ge(0) %}
sameas(value)	Same object reference	{% if x is sameas(y) %}

String Tests

Test	Description	Example
upper	String is uppercase	{% if s is upper %}
lower	String is lowercase	{% if s is lower %}

Collection Tests

Test	Description	Example
empty	Collection is empty	{% if items is empty %}
in(collection)	Value in collection	{% if x is in(items) %}

Boolean Tests

Test	Description	Example
true	Value is true	{% if x is true %}
false	Value is false	{% if x is false %}
truthy	Value is truthy	{% if x is truthy %}
falsy	Value is falsy	{% if x is falsy %}

Examples

Check if variable exists

{% if user is defined %}
  Hello, {{ user.name }}!
{% else %}
  Hello, Guest!
{% endif %}

Alternate row colors

{% for item in items %}
  <tr class="{% if loop.index is even %}even{% else %}odd{% endif %}">
    <td>{{ item.name }}</td>
  </tr>
{% endfor %}

Group items by divisibility

{% for n in numbers %}
  {% if n is divisibleby(3) %}
    <span class="divisible-3">{{ n }}</span>
  {% elif n is divisibleby(2) %}
    <span class="divisible-2">{{ n }}</span>
  {% else %}
    <span>{{ n }}</span>
  {% endif %}
{% endfor %}

Handle empty collections

{% if items is empty %}
  <p>No items found.</p>
{% else %}
  <ul>
    {% for item in items %}
      <li>{{ item }}</li>
    {% endfor %}
  </ul>
{% endif %}

Type checking

{% if value is string %}
  String: {{ value }}
{% elif value is number %}
  Number: {{ value|floatformat:2 }}
{% elif value is sequence %}
  List: {{ value|join:", " }}
{% else %}
  Other: {{ value }}
{% endif %}

Programmatic Access

import { builtinTests } from 'binja'

// All 28 built-in tests
console.log(Object.keys(builtinTests))
// ['divisibleby', 'even', 'odd', 'number', 'integer', 'float',
//  'defined', 'undefined', 'none', 'boolean', 'string', 'mapping',
//  'iterable', 'sequence', 'callable', 'upper', 'lower', 'empty',
//  'in', 'eq', 'ne', 'sameas', 'equalto', 'truthy', 'falsy', ...]