/templates/type/boolean/input.tmpl
Type: /type/template
body: value: $def with (value, property)

$# when checkbox is not selected, browser doesn't send any value to the server.
$# Adding a hidden field sends false value when checkbox is not selected
$# and 2 values when checkbox is selected and the server takes only the latter value.
<input type="hidden" name="$property.name" value="false"/>

$if value.value:
    <input type="checkbox" name="$property.name" value="true" checked="checked"/>
$else:
    <input type="checkbox" name="$property.name" value="true"/>

title: type/boolean/input template