1 KiB
1 KiB
+++ title = "Eww expressions" slug = "Embedded eww expression language" weight = 5 +++
The embedded Eww expression-language
Within variable references, you can make use of a small, built-in expression language.
This can be used whereever you can use variable-references ({{varname}}
).
Example
<button
class="{{if button_active then 'active' else 'inactive'}}"
onclick="toggle_thing">
{{if button_active then 'disable' else 'enable'}}
</button>
Some math: {{12 + 2 * 10}}
Syntax
The expression language supports:
- simple mathematical operations (
+
,-
,*
,/
,%
) - comparisons (
==
,!=
,>
,<
) - boolean operations (
||
,&&
,!
) - elvis operator (
?:
)- if the left side is
""
, then returns the right side, otherwise evaluates to the left side.
- if the left side is
- conditionals (
if condition then 'value' else 'other value'
) - numbers, strings, booleans and variable references (
12
,'hi'
,true
,some_variable
)- strings can contain other expressions again:
'foo {{some_variable}} bar'
- strings can contain other expressions again: