BtIns

filter capitalize

Capitalise the first character and lowercase the rest.

value|capitalize

{{ "hello WORLD"|capitalize }}

filter capfirst

Capitalise only the first character, leaving the rest.

value|capfirst

{{ "hello"|capfirst }}

filter center

Centre the text in a field of the given width.

value|center(width)

width int

field width

{{ "hi"|center(10) }}

filter cut

Remove every occurrence of a substring.

value|cut(arg)

arg string

text to remove

{{ "a-b-c"|cut("-") }}

filter escape

Escape HTML so the text is safe to write. Markup is left as it stands.

value|escape

{{ "<b>"|escape }}

filter e

An alias of escape.

value|e

{{ "<b>"|e }}

filter escapejs

Escape text so it is safe inside a JavaScript string.

value|escapejs

{{ "a'b<c"|escapejs }}

filter forceescape

Escape even text already marked safe.

value|forceescape

{{ ("<b>"|safe)|forceescape }}

filter indent

Indent each line (after the first unless first) by a width.

value|indent(width, first, blank)

width int or string

spaces or a literal prefix

first bool

indent the first line too

blank bool

indent blank lines too

{{ "a\nb"|indent(2) }}

filter linebreaks

Turn newlines into paragraphs and line breaks, returned as safe HTML.

value|linebreaks

{{ "one\n\ntwo"|linebreaks }}

filter linebreaksbr

Turn newlines into line breaks, returned as safe HTML.

value|linebreaksbr

{{ "a\nb"|linebreaksbr }}

filter linenumbers

Prefix every line with its one-based number.

value|linenumbers

{{ "a\nb\nc"|linenumbers }}

filter lower

Lowercase the text.

value|lower

{{ "HELLO"|lower }}

filter markdown

Read the text as Markdown and write it as HTML, the conversion an md template ends with.

value|markdown(safe)

safe bool

escape HTML in the text, true unless you say otherwise

{{ "## From a string"|markdown }}

filter replace

Replace occurrences of old with new, at most count times.

value|replace(old, new, count)

old string

text to find

new string

replacement

count int

most replacements, -1 for all

{{ "a-b-c"|replace("-", " ") }}

filter safe

Mark the text safe; it passes through without escaping.

value|safe

{{ ("<b>"|safe) }}

filter spaceless

Remove the whitespace between tags.

value|spaceless

{{ "<a>  </a>"|spaceless }}

filter string

Cast the value to text.

value|string

{{ 7|string }}

filter striptags

Strip tags and decode entities, collapsing whitespace.

value|striptags

{{ "<b>hi</b>"|striptags }}

filter title

Title-case the text: capitalise each word.

value|title

{{ "hello world"|title }}

filter trim

Strip surrounding characters (default whitespace).

value|trim(chars)

chars string

characters to strip

{{ "  hi  "|trim }}

filter slugify

An ASCII slug: accents dropped, letters and digits kept, spaces and dashes to one dash, lowercase.

value|slugify

{{ "Un éléphant à l'orée!"|slugify }}

filter truncatechars

Cut to a number of characters, ending with an ellipsis; combining marks do not count.

value|truncatechars(arg)

arg int

most characters

{{ "Testing, testing"|truncatechars(8) }}

filter truncate

Cut to a length, ending with an ellipsis, keeping whole words unless killwords.

value|truncate(length, killwords, end, leeway)

length int

maximum length

killwords bool

cut mid-word

end string

the ending, … by default

leeway int

grace before cutting

{{ "a long sentence about the weather"|truncate(20) }}

filter upper

Uppercase the text.

value|upper

{{ "héllo"|upper }}

filter wordcount

Count the words.

value|wordcount

{{ "the quick brown"|wordcount }}

filter wordwrap

Wrap the text at a column width.

value|wordwrap(width, break_long_words, wrapstring, break_on_hyphens)

width int

column width

break_long_words bool

split long words

wrapstring string

line separator

break_on_hyphens bool

break on hyphens

{{ "one two three four five"|wordwrap(10) }}

filter addslashes

Escape quotes and backslashes for a JavaScript string.

value|addslashes

{{ "it's"|addslashes }}

filter iriencode

Percent-encode an IRI for use in a URL.

value|iriencode

{{ "a path/c?d"|iriencode }}

filter phone2numeric

Map letters to the digits of a telephone keypad.

value|phone2numeric

{{ "0800cafe"|phone2numeric }}

filter format

Fill % placeholders with positional or named arguments.

value|format(*args, **named)

args values

positional %s, %d, …

named mapping

named %(name)s

{{ "%s = %s"|format("x", 1) }}

filter abs

The absolute value of a number.

value|abs

{{ -7|abs }}

filter add

Add a number, or concatenate strings and lists.

value|add(arg)

arg value

the value to add or join

{{ 10|add(5) }}

filter filesizeformat

Format a count of bytes as a human size.

value|filesizeformat(binary)

binary bool

use 1024-based units

{{ 1234567|filesizeformat }}

filter float

Parse a number or string as a floating point value.

value|float(default)

default float

fallback when not a number

{{ "3.14"|float }}

filter floatformat

Format a number to fixed places, Django style (g groups thousands, u ungroups).

value|floatformat(arg)

arg string or int

places; -1 drops empty fraction; default -1

{{ 3.14159|floatformat(2) }}

filter get_digit

Return the nth digit of an integer, counting from the right; 1 is the units digit.

value|get_digit(arg)

arg int

which digit

{{ 12345|get_digit(2) }}

filter int

Parse a number or string as an integer, in a given base.

value|int(default, base)

default int

fallback when not a number

base int

number base, 10 by default

{{ "42"|int }}

filter round

Round a number: common, ceil or floor, to a number of places.

value|round(precision, method)

precision int

decimal places

method string

common, ceil or floor

{{ 3.14159|round(2) }}

filter widthratio

Scale a value to a width: the value over the maximum, times the width, rounded half to even.

value|widthratio(max_value, max_width)

max_value number

the value that fills the width

max_width int

the width, 100 by default

{{ 175|widthratio(200) }}

filter sum

Add the items, or a named field of each.

value|sum(attribute, start)

attribute string

field to sum

start value

starting value

{{ items|sum(attribute="n") }}

{"items":[{"n":1},{"n":2},{"n":3}]}

filter batch

Group items into rows of a given size, padding the last with fill_with.

value|batch(linecount, fill_with)

linecount int

items per row

fill_with value

padding for the last row

{{ [1,2,3,4,5]|batch(2)|list }}

filter dictsort

Sort a mapping into (key, value) pairs, by key, value or with a case-sensitive order.

value|dictsort(case_sensitive, by, reverse)

case_sensitive bool

compare letters as written

by string

key or value

reverse bool

reverse the order

{{ {"b":2,"a":1}|dictsort|list }}

filter first

The first item of a sequence.

value|first

{{ [1,2,3]|first }}

filter groupby

Group items that share an attribute, each group read as grouper and list.

value|groupby(attribute, default, case_sensitive)

attribute string

field to group by

default value

value for missing fields

case_sensitive bool

compare letters as written

{{ users|groupby("kind")|map(attribute="grouper")|join(", ") }}

{"users":[{"kind":"a","name":"x"},{"kind":"b","name":"y"},{"kind":"a","name":"z"}]}

filter items

A mapping's entries as (key, value) pairs.

value|items

{{ {"a":1,"b":2}|items|list }}

filter join

Join items with a separator, or a named field of each.

value|join(d, attribute)

d string

the separator

attribute string

field to join

{{ ["a","b","c"]|join(", ") }}

filter last

The last item of a sequence.

value|last

{{ [1,2,3]|last }}

filter length

The length: characters of a string, items of a list, keys of a mapping.

value|length

{{ [1,2,3]|length }}

filter count

An alias of length.

value|count

{{ "hello"|count }}

filter list

Turn the value into a list.

value|list

{{ "abc"|list }}

filter map

Apply a filter to each item, or pull a named field out of each.

value|map(attribute, default, filter)

attribute string

field to read

default value

value for missing fields

filter string

a filter to apply to each item

{{ users|map(attribute="name")|join(", ") }}

{"users":[{"name":"Ada"},{"name":"Grace"}]}

filter max

The largest item, or the largest by a field.

value|max(attribute, case_sensitive)

attribute string

field to compare

case_sensitive bool

compare letters as written

{{ [3,1,2]|max }}

filter min

The smallest item, or the smallest by a field.

value|min(attribute, case_sensitive)

attribute string

field to compare

case_sensitive bool

compare letters as written

{{ [3,1,2]|min }}

filter pprint

A readable, Python-style print of a value.

value|pprint

{{ {"a":[1,2],"b":3}|pprint }}

filter random

One item, chosen so the same page renders the same way twice.

value|random

{{ [1,2,3]|random }}

filter reject

Drop items that pass a test; with no test, drop the untruthy.

value|reject(test, args)

test string

a test name

args values

the test's arguments

{{ [1,2,3,4]|reject("odd")|list }}

filter rejectattr

Drop items whose field fails a test.

value|rejectattr(attribute, test, args)

attribute string

field to test

test string

a test name

args values

the test's arguments

{{ items|rejectattr("shown")|list }}

{"items":[{"shown":true},{"shown":false}]}

filter reverse

Reverse a list, or the characters of a string.

value|reverse

{{ [1,2,3]|reverse|list }}

filter select

Keep items that pass a test; with no test, keep the truthy.

value|select(test, args)

test string

a test name

args values

the test's arguments

{{ [1,2,3,4]|select("odd")|list }}

filter selectattr

Keep items whose field passes a test.

value|selectattr(attribute, test, args)

attribute string

field to test

test string

a test name

args values

the test's arguments

{{ items|selectattr("shown")|list }}

{"items":[{"shown":true},{"shown":false}]}

filter slice

Split into a number of slices, padding the last with fill_with.

value|slice(slices, fill_with)

slices int

how many slices

fill_with value

padding for the last slice

{{ [1,2,3,4,5]|slice(2)|list }}

filter sort

Sort items, by a field, with a case-sensitive or reversed order.

value|sort(reverse, case_sensitive, attribute)

reverse bool

reverse the order

case_sensitive bool

compare letters as written

attribute string

field to sort by

{{ ["b","a","c"]|sort|list }}

filter unique

Drop repeated items, by value or by a field.

value|unique(case_sensitive, attribute)

case_sensitive bool

compare letters as written

attribute string

field to compare

{{ [1,2,2,3]|unique|list }}

filter attr

Read a named attribute of a host object.

value|attr(name)

name string

the attribute

{% set ns = namespace(city="Rome") %}{{ ns|attr("city") }}

filter default

A fallback when the value is undefined, or false under boolean.

value|default(default_value, boolean)

default_value value

what to use instead

boolean bool

also replace a false value

{{ missing|default("none") }}

filter d

An alias of default.

value|d(default_value, boolean)

default_value value

what to use instead

boolean bool

also replace a false value

{{ missing|d("none") }}

filter default_if_none

A fallback used only when the value is null.

value|default_if_none(arg)

arg value

what to use instead

{{ none|default_if_none("none") }}

filter urlencode

Percent-encode a string, or a mapping or pairs as a query string.

value|urlencode

{{ {"q":"a b"}|urlencode }}

filter urlize

Turn web addresses and emails into anchor tags.

value|urlize(trim_url_limit, nofollow, target, rel, extra_schemes)

trim_url_limit int

shorten shown links

nofollow bool

add rel=nofollow

target string

the anchor target

rel string

extra rel words

extra_schemes list

more URI schemes to link

{{ "visit http://example.com"|urlize }}

filter xmlattr

Build a string of attributes from a mapping, as safe markup.

value|xmlattr(autospace)

autospace bool

a leading space, on by default

{{ {"class":"x","id":5}|xmlattr }}

filter tojson

Serialise a value to JSON safe inside a script tag.

value|tojson(indent)

indent int

spaces to indent

{{ {"a":1}|tojson }}

filter json_script

Wrap JSON in a script tag, optionally with an id.

value|json_script(element_id)

element_id string

the tag's id

{{ {"a":1}|json_script("data") }}

filter truncatewords

Cut to a number of words, ending with an ellipsis.

value|truncatewords(arg)

arg int

most words

{{ "one two three four"|truncatewords(2) }}

filter truncatechars_html

Cut marked-up text to a number of characters, closing the elements the cut leaves open; the result is markup when the input is trusted.

value|truncatechars_html(arg)

arg int

most characters, tags aside

{{ ("<p>one <b>two</b> three</p>"|safe)|truncatechars_html(8) }}

filter truncatewords_html

Cut marked-up text to a number of words, closing the elements the cut leaves open; the result is markup when the input is trusted.

value|truncatewords_html(arg)

arg int

most words

{{ ("<p>one <b>two</b> three</p>"|safe)|truncatewords_html(2) }}

filter unordered_list

Render a list of items and nested lists as HTML ul elements.

value|unordered_list

{{ tree|unordered_list }}

{"tree":["first",["child one","child two"],"last"]}

filter ljust

Left-justify the text in a field of the given width.

value|ljust(arg)

arg int

field width

{{ "hi"|ljust(5) }}

filter rjust

Right-justify the text in a field of the given width.

value|rjust(arg)

arg int

field width

{{ "hi"|rjust(5) }}

filter yesno

Map true, false and null to words, comma-separated.

value|yesno(arg)

arg string

yes,no,maybe (maybe optional)

{{ ok|yesno }}

{"ok":true}

filter pluralize

Add a suffix (or two, comma-separated) based on a count.

value|pluralize(arg)

arg string

suffix, or singular,plural

{{ count|pluralize }}

{"count":3}

filter date

Format a date with Django's letters; a time letter is refused.

value|date(arg)

arg string

a format or a named format such as DATE_FORMAT

{{ d|date("Y-m-d") }}

{"d":"2026-05-04"}

filter time

Format a time with Django's letters; a date letter is ignored.

value|time(arg)

arg string

a format or TIME_FORMAT

{{ t|time("H:i") }}

{"t":"2026-05-04T13:45:00"}

filter timesince

Words for the span from a date to now (a date you supply, templates read no clock).

value|timesince(now, depth)

now date

the moment to measure to

depth int

most adjacent units, 2 by default

{{ d|timesince(now) }}

{"d":"2026-01-01","now":"2026-05-04"}

filter timeuntil

Words for the span from now to a date.

value|timeuntil(now, depth)

now date

the moment to measure to

depth int

most adjacent units, 2 by default

{{ d|timeuntil(now) }}

{"d":"2026-05-04","now":"2026-01-01"}

test none

True when the value is null.

value is none

{{ none is none }}

test boolean

True when the value is a boolean.

value is boolean

{{ true is boolean }}

test true

True when the value is the boolean true.

value is true

{{ true is true }}

test false

True when the value is the boolean false.

value is false

{{ false is false }}

test integer

True when the value is an integer.

value is integer

{{ 3 is integer }}

test float

True when the value is a floating point number.

value is float

{{ 3.0 is float }}

test number

True when the value is a number (integer, float or boolean).

value is number

{{ 3 is number }}

test string

True when the value is text or safe markup.

value is string

{{ "x" is string }}

test mapping

True when the value is a mapping.

value is mapping

{{ {} is mapping }}

test sequence

True when the value is a string, list, tuple or mapping.

value is sequence

{{ [1,2] is sequence }}

test iterable

True when the value can be looped over.

value is iterable

{{ "ab" is iterable }}

test callable

True when the value can be called, like a global function.

value is callable

{{ range is callable }}

test escaped

True when the value is markup already safe to write.

value is escaped

{{ ("<b>"|safe) is escaped }}

test odd

True when a number is odd.

value is odd

{{ 7 is odd }}

test even

True when a number is even.

value is even

{{ 4 is even }}

test divisibleby

True when a number divides by the argument.

value is divisibleby(n)

n number

the divisor

{{ 9 is divisibleby(3) }}

test ==

True when the value equals the other. Also eq and equalto.

value == other

other value

what to compare against

{{ 3 == 3 }}

test eq

An alias of ==.

value is eq other

other value

what to compare against

{{ 3 is eq 3 }}

test equalto

An alias of ==.

value is equalto other

other value

what to compare against

{{ 3 is equalto 3 }}

test !=

True when the value differs from the other. Also ne.

value != other

other value

what to compare against

{{ 3 != 4 }}

test ne

An alias of !=.

value is ne other

other value

what to compare against

{{ 3 is ne 4 }}

test <

True when the value is less than the other. Also lt and lessthan.

value < other

other value

what to compare against

{{ 3 < 4 }}

test lt

An alias of <.

value is lt other

other value

what to compare against

{{ 3 is lt 4 }}

test lessthan

An alias of <.

value is lessthan other

other value

what to compare against

{{ 3 is lessthan 4 }}

test >

True when the value is greater than the other. Also gt and greaterthan.

value > other

other value

what to compare against

{{ 3 > 2 }}

test gt

An alias of >.

value is gt other

other value

what to compare against

{{ 3 is gt 2 }}

test greaterthan

An alias of >.

value is greaterthan other

other value

what to compare against

{{ 3 is greaterthan 2 }}

test <=

True when the value is at most the other. Also le.

value <= other

other value

what to compare against

{{ 3 <= 3 }}

test le

An alias of <=.

value is le other

other value

what to compare against

{{ 3 is le 3 }}

test >=

True when the value is at least the other. Also ge.

value >= other

other value

what to compare against

{{ 3 >= 3 }}

test ge

An alias of >=.

value is ge other

other value

what to compare against

{{ 3 is ge 3 }}

test lower

True when text is all lowercase.

value is lower

{{ "abc" is lower }}

test upper

True when text is all uppercase.

value is upper

{{ "ABC" is upper }}

test sameas

True when the two values are the same object or equal value.

value is sameas other

other value

the other value

{% set a = [1] %}{{ a is sameas a }}

test in

True when the value is a member of the container.

value is in container

container value

where to look

{{ "a" in ["a","b"] }}

test defined

True when the name resolved to a value.

value is defined

{% set present = 1 %}{{ present is defined }}

test undefined

True when the name resolved to nothing.

value is undefined

{{ missing is undefined }}

test filter

True when a filter of the given name is registered.

value is filter

{{ "upper" is filter }}

test test

True when a test of the given name is registered.

value is test

{{ "odd" is test }}

global range

Build a list of integers, Python's range.

range(stop) · range(start, stop) · range(start, stop, step)

start int

first value, 0 by default

stop int

one past the last

step int

the step, 1 by default

{{ range(1, 4)|list }}{{ range(0, 10, 2)|list }}

global dict

Build a mapping from pairs, a mapping or named arguments.

dict(pairs) · dict(a=1, b=2)

pairs sequence

a list of [key, value]

named values

keys and values

{{ dict(a=1, b=2)|items|list }}

global lipsum

Generate pseudo-Latin filler text, the same page twice, as safe HTML or plain text.

lipsum(n, html, min, max)

n int

paragraphs, 5 by default

html bool

wrap in <p>, true by default

min int

shortest word count

max int

longest word count

{{ lipsum(n=1, min=5, max=8) }}

global cycler

Cycle through items: current names the present item, next advances.

cycler(*items)

items values

the values to cycle

{% set c = cycler("odd","even") %}{{ c.next() }}{{ c.next() }}{{ c.next() }}

global joiner

A separator that prints nothing the first time and the separator after.

joiner(sep)

sep string

the separator, ", " by default

{% set j = joiner(", ") %}{% for x in ["a","b","c"] %}{{ j() }}{{ x }}{% endfor %}

global namespace

A mapping whose fields a template may assign from inside a loop or block.

namespace(**fields)

fields values

initial fields

{% set ns = namespace(n=0) %}{% for i in [1,2,3] %}{% set ns.n = ns.n + i %}{% endfor %}{{ ns.n }}

global gettext

Translate a message through the translation seam; with no seam the text stands.

gettext(message) · _(message)

message string

the message to translate

{{ gettext("Hello") }} {{ _("World") }}

global _

An alias of gettext.

_(message)

message string

the message to translate

{{ _("Hello") }}

global ngettext

Translate a singular or plural message by a count.

ngettext(singular, plural, count)

singular string

one form

plural string

many form

count number

the count

{{ ngettext("%(num)d apple", "%(num)d apples", n) }}

{"n":2}

global pgettext

Translate a message within a context.

pgettext(context, message)

context string

the message context

message string

the message to translate

{{ pgettext("menu", "Open") }}

global npgettext

Translate a singular or plural message within a context.

npgettext(context, singular, plural, count)

context string

the message context

singular string

one form

plural string

many form

count number

the count

{{ npgettext("file", "%(num)d file", "%(num)d files", n) }}

{"n":2}

global templatetag

Write the characters of a tag as text, by Django's name for each.

templatetag(tag)

tag string

openblock, closeblock, openvariable, closevariable, openbrace, closebrace, opencomment or closecomment

{{ templatetag("openblock") }} if x {{ templatetag("closeblock") }}

global query_string

Build a query string from mappings and named values; null drops a key, a list repeats it.

query_string(*mappings, **values)

mappings mapping

the parameters to start from

values values

the parameters to set

{{ query_string(page=2, q="a b") }}

global url

The address a program gives a route. Registered by the program through Env::add_host, so it is shown here rather than run.

url(name, *args, **kwargs)

name string

the route's name

args values

what fills the route

{{ url("post", 42) }}

global static

Where a static file is served from. Registered by the program through Env::add_host.

static(path)

path string

the file under the static root

{{ static("css/site.css") }}

global static_prefix

The prefix static files sit under, on its own. Registered by the program.

static_prefix()

{{ static_prefix() }}

global media_prefix

The prefix uploaded files sit under. Registered by the program.

media_prefix()

{{ media_prefix() }}

global csrf_token

The token a form carries, as markup. Registered by the program.

csrf_token()

{{ csrf_token() }}

global now

The moment to render, written with Django's date letters. Registered by the program: templates read no clock.

now(format)

format string

a format, or a named one such as DATE_FORMAT

{{ now("Y-m-d H:i") }}

statement if

Branch on a condition; elif adds a clause, else the fallback.

{% if cond %}…{% elif cond %}…{% else %}…{% endif %}

{% if n > 2 %}big{% elif n == 2 %}two{% else %}small{% endif %}

{"n":2}

statement for

Loop over items. The else runs when there were none; break and continue work inside. The loop variable holds index, index0, revindex, first, last, length, depth, previtem, nextitem, cycle(…) and changed(…); a recursive loop calls loop(children).

{% for x in items %}…{% else %}…{% endfor %}

items sequence

what to iterate

if condition

loop only matching items

recursive flag

descend into nested items

{% for x in items %}{{ loop.index }}:{{ x }}{% if not loop.last %}, {% endif %}{% else %}none{% endfor %}

{"items":["a","b","c"]}

statement set

Bind a name to a value, or to a block of markup with endset.

{% set name = expr %} · {% set name %}…{% endset %}

name name

the variable

expr value

a value or filter chain

block flag

a block form with endset

{% set greeting %}Hello {{ name }}{% endset %}{{ greeting }}

{"name":"Ada"}

statement with

Give names local values for the enclosed block.

{% with a = 1, b = 2 %}…{% endwith %}

names assignments

names and their values

{% with total = 3 %}{{ total }}{% endwith %}

statement macro

Define a reusable block with parameters; call it by name, or with a caller block via endcall.

{% macro name(args) %}…{% endmacro %} · {% call name(args) %}…{% endcall %}

args parameters

names, defaults, a rest parameter

{% macro field(n, v="") %}<input name="{{ n }}" value="{{ v }}">{% endmacro %}{{ field("q") }}

statement filter

Apply a filter to a block of markup.

{% filter upper %}…{% endfilter %}

filter filter

the filter and its arguments

{% filter upper %}hello {{ name }}{% endfilter %}

{"name":"ada"}

statement block

Define a named block a parent can fill; super() calls the parent's block, scoped sees the loop around it, required must be filled, append and prepend add to it. The indentation syntax has block append and block prepend too. Needs a loader through Env::new(load=…).

{% extends "base" %} · {% block name %}…{% endblock %}

{% extends "layout.html" %}
{% block body %}page{% endblock %}

statement include

Pull in another template; ignore missing tolerates a missing file, with context shares the names, inline renders in place, raw includes plain text, and a block lands where the included file says yield. Needs a loader.

{% include "partial" %} · {% include "partial" ignore missing with context %}

missing flag

ignore a missing file

context flag

share local names

inline flag

render in place

raw flag

include as text

{% include "footer.html" ignore missing %}

statement import

Import names from another template as a module, or bring chosen names in directly; with context shares the names. Needs a loader.

{% import "ui" as ui %} · {% from "ui" import card %}

context flag

share local names

{% from "ui.html" import card %}{{ card("Title", "Note") }}

statement raw

Write text exactly as written, with no substitution.

{% raw %}…{% endraw %}

{% raw %}{{ not_evaluated }}{% endraw %}

statement autoescape

Turn escaping on or off for the enclosed block.

{% autoescape false %}…{% endautoescape %}

flag bool

escape or not

{% autoescape false %}{{ html }}{% endautoescape %}

{"html":"<b>"}

statement show

Write the block either way; when the condition is false it is hidden with an inline style, not removed.

{% show cond %}…{% endshow %}

cond bool

whether to show

{% show ok %}<b>shown</b>{% endshow %}

{"ok":true}

statement debug

Print the current context: every name in scope.

{% debug %}

{% debug %}

statement trans

Mark text for translation; pluralize switches on a count. With no translation seam the source text stands.

{% trans %}…{% endtrans %} · {% trans count=n %}…{% pluralize %}…{% endtrans %}

count number

the plural count

context string

a message context

{% trans count=n %}{{ count }} item{% pluralize %}{{ count }} items{% endtrans %}

{"n":3}

statement do

Evaluate an expression for its side effect, typically calling a method of a host object.

{% do object.method() %}

expr call

a callable to run

{% do user.log("visited") %}

statement once

Render a block once and, with a cache passed to Env::new, keep it; without one it renders every time.

{% once key %}…{% endonce %}

key value

the cache key

{% once "sidebar" %}{{ 1 + 1 }}{% endonce %}