Derive Macro EmbeddedForm 

#[derive(EmbeddedForm)]
{
    // Attributes available to this derive:
    #[form]
}

Derives EmbeddedForm for an embedded struct or enum.

Builds the schema node and converts the value through that node’s keys.

#[derive(Debug, Clone, toasty::Embed, tablo_core::EmbeddedForm)]
pub enum Publication {
    #[column(variant = 1)]
    Scheduled {
        #[shared(timestamp)]
        #[form(label = "Publication timestamp")]
        scheduled_at: String,
        scheduled_for: String,
    },
    #[column(variant = 2)]
    Published {
        #[shared(timestamp)]
        published_at: String,
        canonical_url: String,
    },
}

// form declaration — no field bindings written by hand
Section::new("Publication").schema(Publication::form(Post::fields().publication()));

How a field is classified

A field marked #[form(embed)] is another embedded value, delegated to its own EmbeddedForm. Every other field is a scalar: one column, read and written through FormScalar (String, a TypedValue type, or an Option of one). A scalar of another type fails to compile at the field, naming the trait. An empty scalar is its declared #[form(blank = ..)], else its FormScalar::blank(); with neither, the parse refuses its key.

Which variant an enum reads

A named discriminant always wins, and an undeclared one is refused; otherwise the first variant, in declaration order, with a payload of its own submitted — a #[shared(..)] column belongs to several variants and never selects one; otherwise the first variant.

Per-field attributes

• #[form(embed)] — a nested EmbeddedForm value.
• #[form(label = "Canonical URL")] — the control’s label (default: the field name, humanized).
• #[form(multiline = 3)] — a <textarea> of 3 rows.
• #[form(blank = ..)] — what an empty submission reads as, overriding the leaf type’s own answer.

Anything else in #[form(..)] is a compile error, as are label, multiline, and blank on an embedded value. Derives EmbeddedForm for an embedded struct or enum; documented on the tablo-core re-export.