Function field 

pub fn field(
    id: impl Into<String>,
    placeholder: impl Into<String>,
    value: impl Into<String>,
    kind: FieldKind,
    error: Option<String>,
) -> Widget

A text field with full control over FieldKind and an optional inline validation error. The kind-specific helpers below (secure_field, email_field, …) wrap this for the common cases.