Documentation

Field types with Override1 modifiers applied: an h a field whose config names a modifier m becomes m a (so its Rep1 leaf is Rec1 m); all other fields are unchanged. Used by both rewriteRep1 (the Rep1 type) and synthGeneric1 (the from1/to1 values), keeping them in lock-step.

Rewrite Rep1 (Stock1 F) to the parameter-aware structure (Par1/Rec1/ Rec0 leaves under the M1 metadata). No rewrite if any field is an unsupported shape (composition etc.).

The structural Rep for a whole datatype: a single constructor is just its product repStruct; several constructors form a balanced :+: tree of their product structs (mirroring GHC's foldBal). cons carries each constructor's modifier field types (ciFields) and the per-cell coercions (ciFieldCos, realFieldType ~R modifierType; Refl without an Override). The Rep leaves use the modifier types (matching rewriteRep); from coerces the real field into the leaf, to coerces back before rebuilding. Refl everywhere ⇒ byte-identical Core to plain.

Synthesize Generic1 (Stock1 F): like synthGeneric but the field representation is parameter-aware — the last type variable a becomes Par1, g a becomes Rec1 g, a constant becomes Rec0 (see rep1Field). from1/to1 wrap/unwrap each field through the corresponding newtype. Nothing for shapes rep1Field rejects (e.g. composition f (g a)).