Extracts nested opts from :keys vector.

Returns map of {field-keyword -> nested-opts-or-nil}. Returns empty map {} for empty vector (filters everything out). Returns nil for nil input (no filtering).

E.g. [:amount {:currency {:keys :id :numeric}}] => {:amount nil, :currency {:keys :id :numeric}}

Filters map m to only include keys from keys-spec.

For keys with nested opts, applies those opts recursively via serializer-fn.

Creates Money from currency and amount for deserialization.

When rescale is provided (non-nil integer), the Currency object is cloned with that scale instead of using its nominal scale. This allows deserializing data with a different precision than the registry currency defines.

The rounding-mode can be a RoundingMode, keyword, or string - it will be parsed using scale/post-parse-rounding. If not provided, falls back to scale/*rounding-mode* or throws on precision loss.

Arguments: - currency - Currency object or identifier (keyword, string) - amount - BigDecimal amount - registry - Registry to use for currency lookup - rounding-mode - optional rounding mode (RoundingMode, keyword, or string) - rescale - optional target scale (overrides currency’s nominal scale)

Parses a value to BigDecimal.

Accepts: - nil -> nil - BigDecimal -> as-is - integer -> BigDecimal/valueOf - number -> BigDecimal/valueOf (note: doubles lose precision) - string -> parsed via bigdec (trims whitespace, removes underscores)

Throws ExceptionInfo on invalid input. The op-kw argument is used in error messages to identify the calling operation.

Rescales a BigDecimal amount to the given scale for serialization.

When rescale is nil, returns the amount as-is. When rescale is provided, rescales using the given rounding-mode or falls back to scale/*rounding-mode* or UNNECESSARY.

The rounding-mode can be a RoundingMode, keyword, or string.