Fix OCaml type inference in List.fold_left lambda - #19
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Add explicit type annotation (pos:position) inside the fold_left lambda. OCaml's type inference determines element type from field access inside lambdas, not from the parameter annotation. Since both position and price_level types have a 'quantity' field, OCaml was inferring price_level based on definition order in types.ml. The fix: annotate the lambda parameter directly: List.fold_left (fun acc (pos:position) -> ...) This ensures OCaml knows pos is of type position when accessing pos.quantity.
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Add explicit type annotation (pos:position) inside the fold_left lambda. OCaml's type inference determines element type from field access inside lambdas, not from the parameter annotation. Since both position and price_level types have a 'quantity' field, OCaml was inferring price_level based on definition order in types.ml.
The fix: annotate the lambda parameter directly:
List.fold_left (fun acc (pos:position) -> ...)
This ensures OCaml knows pos is of type position when accessing pos.quantity.