How to set a default value for column based on another column?

For example, if I had this schema:

export const posts = sqliteTable({
  id: integer("id").primaryKey(),
  title: text("title"),
  slug: text("slug").default(/* ??? */),
});

export const posts = sqliteTable({
  id: integer("id").primaryKey(),
  title: text("title"),
  slug: text("slug").default(/* ??? */),
});

export const posts = sqliteTable({
  id: integer("id").primaryKey(),
  title: text("title"),
  slug: text("slug").default(/* ??? */),
});

export const posts = sqliteTable({
  id: integer("id").primaryKey(),
  title: text("title"),
  slug: text("slug").default(/* ??? */),
});

How could I make the

slug

slug

slug

slug column's default be determined based on

title

title

title

title via a slugify function?