Conditions — show values and blocks only when they apply
Show a value, a block's text or a whole block only when rules hold: a Buy button only when there's a buy link, "First published 1965" only when the year is set, a badge only for recent posts. Built with a rule builder in the TAW data popup; checked live on the front end.
Show it only when it applies
Some content only makes sense when a value is set, or only for some posts:
- a Buy this book button only when the book has a buy link;
- "· First published 1965" only when the year is known;
- a "New" badge only for posts from the last 30 days;
- "Welcome back" for logged-in visitors, "Sign in" for everyone else.
A condition is a set of rules. When they hold, the value or block shows; when they don't, it doesn't (or a value shows other text instead). Every page view checks them with the post's current values, and inside a Query Loop each item decides for itself.
Conditions ship with taw/core v1.66.0 (front end) and v1.67.0 (the editor). They work in both TAW Theme and TAW Gutenberg, on top of dynamic tags and Block Bindings.
Show a whole block only when…
Select the block
Any block works: a paragraph, a button group, an image, a whole group of blocks.
Open its visibility settings
Either click the TAW data button (a database icon) in the toolbar and open the Visibility tab, or open TAW visibility in the block's sidebar (every block has it). Click Add a condition.
Build the rules
Each rule is a value, a comparison and, for most comparisons, what to compare with:
Buy link · is not empty
The answer shows right away: Shown for this post or Hidden for this post. In the canvas the block gets a dashed outline and a label, and it's dimmed while it's hidden for the post you're editing.
To stop, click Remove condition.
Show a value only when…
On the TAW data popup's Expression tab, or in the editor of a value already in the text (click it), use Show only when…:
- build the rules the same way;
- Otherwise show is the text shown when the rules don't hold. Leave it empty to show nothing.
A value with a condition has a dashed border in the editor. It keeps showing its value there; the front end decides.
This works for values inside text and for a block's whole text (Insert as → Block text).
Rules
Values
Pick any value the popup lists: the post's fields, post and site properties, options, term and author fields. Two more are made for conditions:
| Value | Is |
|---|---|
Logged in (@viewer.logged_in) | yes for logged-in visitors |
Role (@viewer.role) | the visitor's roles, e.g. editor, author |
Today / Now (@date.today, @date.now) | the current date, or date and time |
Custom value… takes any single expression value, functions included, e.g.
@post.date.format('l') to compare the weekday.
Comparisons
| Kind | Comparisons | Compare with |
|---|---|---|
| Presence | is empty, is not empty | — |
| Text | is, is not, contains, does not contain, starts with, ends with | text; case and outer spaces don't matter |
| Lists | is one of, is not one of | a list: fiction, poetry |
| has the item, does not have the item | one item of a multi-value field (checkboxes) | |
| Numbers | is greater than, is at least, is less than, is at most, is between | numbers |
| Dates | is after, is before, is on, is between the dates | a date (2025-01-31), today, now, tomorrow, yesterday, or relative (-30 days, +1 week) |
| Yes / no | is yes / on, is no / off | — (empty, 0, no, off and false are "no") |
Date fields and the post date are compared as dates, in the site's time zone. To compare with another
value, write it with @: @book_year is @first_edition_year. Write @@ for a literal @.
All or any, and groups
Show … when all / any of these are true combines the rules. Add group adds a group with its own all/any, for "this, and one of those":
Type is
book, and any of: Logged in is yes · Price is less than300
Groups go one level deep, with up to 20 rules in total.
Good to know
- Hidden isn't private. A hidden block is left out of the page, but it's still in the post content (and in the template). Use conditions for what shows, not for who may read it.
- Page caches. Rules on Logged in or Role differ per visitor. They work with caches that don't serve cached pages to logged-in users (most do that). Rules on the post's own values are cache-safe.
- Templates. In the Site Editor, "for this post" means the latest post of the template's type, as the field previews do.
- If a rule is incomplete (no comparison, nothing to compare with), the builder says which rule, and the block or value stays hidden until it's fixed.
- Privacy is the same as for values: a field with
"bindings": false, or a private post's fields, read as empty.
How it's stored
A condition is JSON; the builder writes it for you.
{"match": "all", "rules": [
{"value": "@book_buy_link", "op": "not_empty"},
{"match": "any", "rules": [
{"value": "@viewer.logged_in", "op": "is_true"},
{"value": "@price", "op": "lt", "to": 300}
]}
]}
| On | Where |
|---|---|
| A whole block | "metadata": {"tawShowIf": {…}} |
| A value in text | data-taw-tag='{"expr": "…", "if": {…}, "else": "…"}' |
| A block's text | the binding's args: {"expr": "…", "if": {…}, "else": "…"} |
Operators in JSON: empty, not_empty, equals, not_equals, contains, not_contains, starts_with,
ends_with, in, not_in, has, has_not, gt, gte, lt, lte, between, before, after, on,
between_dates, is_true, is_false. If taw/core is ever removed, blocks with a condition always show and
values keep their last text.
TAW Gutenberg's single-book.html template is a working example: the subtitle, "First published …" and a
Buy this book button each show only when their value is set.