/Knowledge/sources/honojs__hono/llms-full/css-helper-createcsscontext-oninvalidslug--b4eea2cb8634.md
css Helper: createCssContext > onInvalidSlug - hono-docs
css Helper: createCssContext onInvalidSlug Source evidence: /Sources/honojs hono/provenance.md Canonical citation: https://hono.dev/llms full.txt oninvalidsl...
css Helper: createCssContext > onInvalidSlug
Source evidence: /Sources/honojs__hono/provenance.md Canonical citation: https://hono.dev/llms-full.txt#oninvalidslug
Summary
If the classNameSlug function returns an invalid CSS class name, a warning is logged by default. You can customize this behavior with onInvalidSlug. ```ts const { css, Style } = createCssContext({ id: 'my-styles', classNameSlug: (has...
Content
If the classNameSlug function returns an invalid CSS class name, a warning is logged by default. You can customize this behavior with onInvalidSlug.
const { css, Style } = createCssContext({
id: 'my-styles',
classNameSlug: (hash, label) => label || hash,
onInvalidSlug: (slug) => {
throw new Error(`Invalid CSS class name: ${slug}`)
},
})
Metadata
{
"chunk_index": 0,
"citation": "https://hono.dev/llms-full.txt#oninvalidslug",
"coverage_role": "overview",
"qualified_title": "Hono / llms-full / css Helper > `createCssContext` > `onInvalidSlug`",
"retrieved_at": "2026-07-02T05:51:01Z",
"section_index": 703,
"source_id": "/honojs/hono",
"source_type": "llms_full",
"target_label": "llms-full",
"title": "css Helper: createCssContext > onInvalidSlug",
"upstream_url": "https://hono.dev/llms-full.txt",
"version": "2026"
}