Module minijinja::filters

Filter functions and abstractions.

MiniJinja inherits from Jinja2 the concept of filter functions. These are functions which are applied to values to modify them. For example the expression {{ 42|filter(23) }} invokes the filter filter with the arguments 42 and 23.

MiniJinja comes with some built-in filters that are listed below. To create a custom filter write a function that takes at least a &State and value argument, then register it with add_filter.

Custom Filters

A custom filter is just a simple function which accepts inputs as parameters and then returns a new value. For instance the following shows a filter which takes an input value and replaces whitespace with dashes and converts it to lowercase:

fn slugify(_state: &State, value: String) -> Result<String, Error> {
    Ok(value.to_lowercase().split_whitespace().collect::<Vec<_>>().join("-"))
}

env.add_filter("slugify", slugify);

MiniJinja will perform the necessary conversions automatically via the FunctionArgs and Into traits.

Traits

Filter

A utility trait that represents filters.

Functions

absbuiltins

Returns the absolute value of a number.

batch

Batch items.

defaultbuiltins

Checks if a string starts with another string.

dictsortbuiltins

Dict sorting functionality.

escape

HTML escapes a string.

firstbuiltins

Returns the first item from a list.

itemsbuiltins

Returns a list of pairs (items) from a mapping.

joinbuiltins

Joins a sequence by a character

lastbuiltins

Returns the last item from a list.

lengthbuiltins

Returns the “length” of the value

listbuiltins

Converts the input value into a list.

lowerbuiltins

Converts a value to lowercase.

replacebuiltins

Does a string replace.

reversebuiltins

Reverses a list or string

roundbuiltins

Round the number to a given precision.

safe

Marks a value as safe. This converts it into a string.

slice

“”“Slice an iterator and return a list of lists containing those items. Useful if you want to create a div containing three ul tags that represent columns:

titlebuiltins

Converts a value to title case.

tojsonbuiltins and json

Dumps a value to JSON.

trimbuiltins

Trims a value

upperbuiltins

Converts a value to uppercase.

urlencodebuiltins and urlencode

URL encodes a value.