[ @sdxc/u/general ]
var
Resolves a custom property reference: var(--{name}), or with a fallback, var(--{name}, {fallback}).
import { var } from "@sdxc/u/general";Quick reference
Every documented call, beside the CSS it emits.
| Call | CSS |
|---|---|
u.var("sidebar-width") | "var(--sidebar-width)" |
u.var("sidebar-width", "18rem") | "var(--sidebar-width, 18rem)" |
Examples
Basic example
Use u.var(name, fallback) to read a custom property in any utility that takes a CSS value; it is written u.var because var is a reserved word:
<div mix={[hstack({ gap: 4 })]}>
<aside mix={[is(u.var("sidebar-width", "12rem")), ...]}>sidebar</aside>
<main mix={[grow(), ...]}>main</main>
</div>Setting it from a parent
Set the property on an ancestor with u.vars() and every u.var() below it picks the value up, so one layout adapts by context:
<div mix={[...]}>
<div mix={[hstack({ gap: 4 })]}>
<aside mix={[is(u.var("sidebar-width", "12rem")), ...]}>12rem</aside>
<main mix={[grow(), ...]}>main</main>
</div>
<div mix={[u.vars({ "sidebar-width": "20rem" }), hstack({ gap: 4 })]}>
<aside mix={[is(u.var("sidebar-width", "12rem")), ...]}>20rem</aside>
<main mix={[grow(), ...]}>main</main>
</div>
</div>Applying on a state
Wrap the call in a state utility to scope it to one selector.
u.hover(u.var("sidebar-width"))Responsive design
Wrap the call in a container query to scope it to one width.
u.at("md", u.var("sidebar-width"))Signature
u.var(name: string, fallback?: string)