Modifiers reference

Modifiers change a tag's value: @post(title).uppercase(). Chain as many as you need; they run left to right. Arguments in brackets are optional unless noted.

Text

Modifier	What it does
uppercase(), lowercase()	Changes the case.
capitalize()	Capitalizes the first letter.
truncate(length, suffix)	Shortens to a number of characters (default 100), adding a suffix (default …).
truncate_words(words, suffix)	Shortens to a number of words (default 20).
prepend(text), append(text)	Adds text before or after, only when the value isn't empty.
replace(search, replace)	Replaces text.
strip_tags()	Removes HTML tags.
slugify()	Turns text into a URL-friendly slug.
pluralize(singular, plural, include_value)	Picks a word by the number: @post(reviews).pluralize("review", "reviews").
trim()	Removes spaces at the start and end.

Numbers

Modifier	What it does
number_format(decimals)	Formats with the site's thousands and decimal separators.
currency_format(currency, in_cents, always_fraction)	Formats as money. The currency is an ISO code such as EUR; the default is USD unless your site changes it. Set in_cents when the number is stored in cents.
round(precision)	Rounds to a number of decimals (default 0).
clamp(min, max)	Keeps the number within a range.
abbreviate(precision)	12400 becomes 12.4K.
ordinal()	2 becomes 2nd.

Dates

Modifier	What it does
date_format(format)	Formats a date using WordPress date format characters, in the site's time zone and language. Default F j, Y.
date_modify(change)	Shifts a date: "+1 day", "-2 weeks".
time_diff(timezone)	How long until or since the date, such as 3 days. Write "ago" or "in" around it yourself.
to_age()	Years since the date, for example a birth date.

Lists

Modifier	What it does
first(), last()	The first or last item.
nth(index)	One item, counting from 0.
count()	How many items there are.
list(separator, last_separator, prefix, suffix)	Joins the items: .list(", ", " and ") gives "Ana, Bruno and Carla".
shuffle()	Random order.
loop_index(base)	Inside a data loop, the item's position (starting at 1, or at the base you give). Offsets keep counting, so the first item shown after skipping two is 3.

Fallbacks

fallback(value) shows another value when this one is empty: @post(subtitle).fallback(@post(title)).

Conditions

Conditions check the value and pass or fail. On their own they output nothing useful; combine them with then() and else():

@post(stock).is_less_than(5).then("Almost gone!").else("")

Condition	Passes when the value…
is_empty(), is_not_empty()	is empty / has a value
is_checked(), is_unchecked()	is on / off (Switcher)
is_equal_to(value), is_not_equal_to(value)	equals / doesn't equal
is_greater_than(value), is_greater_than_or_equal(value), is_less_than(value), is_less_than_or_equal(value)	compares as a number
is_between(start, end)	is within a range
is_one_of(values)	matches one of several values
contains(value), does_not_contain(value), starts_with(value), ends_with(value)	contains or starts or ends with text
matches(pattern)	matches a regular expression
is_past(), is_future(), is_today()	is a date before, after, or on today
is_first(), is_last()	is the first or last item shown in a loop

The same conditions are used by the Dynamic tag rule in visibility.

Previews that take a moment

Most modifiers run instantly in the editor. A few need the server to calculate, so their preview can take a moment to appear: date formatting and date calculations, currency formatting, strip_tags(), slugify(), shuffle(), #math variables, and all conditions. The published page always shows the final result.

Technical details for LLMs

• Keys by group: text uppercase, lowercase, capitalize, truncate, truncate_words, prepend, append, replace, strip_tags, slugify, pluralize; number number_format, currency_format, round, clamp, abbreviate, ordinal; date date_format, date_modify, time_diff, to_age, is_past, is_future, is_today; list first, last, nth, count, list, shuffle, loop_index; general fallback, trim; let; conditionals is_empty, is_not_empty, is_checked, is_unchecked, is_equal_to, is_not_equal_to, is_greater_than, is_greater_than_or_equal, is_less_than, is_less_than_or_equal, is_between, is_one_of, contains, does_not_contain, starts_with, ends_with, matches, is_first, is_last, then, else.
• Server-only (not client-resolvable): date_format, date_modify, time_diff, to_age, currency_format, strip_tags, slugify, shuffle, let, and every conditional.
• is_first / is_last / loop_index read the loop level named by the tag they're attached to; outside a loop the conditions fail.
• Currency default: filter vxframework/dynamic-data/default_currency (default USD); override rendering with vxframework/dynamic-data/currency_format.
• Live list with argument schemas: vx-framework/get-dynamic-data-catalog. Register modifiers with vxframework/dynamic-data/modifiers (see Developers → Extending).