package petrol

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Module Petrol.TypeSource

Sourcetype 'a t

Represents an SQL data type that maps to an OCaml type 'a.

Sourceval pp : Format.formatter -> 'a t -> unit
Sourceval show : 'a t -> string
Sourceval custom : ty:'a Caqti_type.t -> repr:string -> 'a t

custom ~ty ~repr creates a new SQL type that is represented by the Caqti type ty, and is represented in a SQL query as repr.

For example, you might define the BOOL datatype as follows:

  let bool = Type.custom ~ty:Caqti_type.bool ~repr:"BOOLEAN"

Note Petrol doesn't implement the boolean type using this function, and uses a slightly more efficient internal encoding, but for more bespoke custom user types this function should be sufficient.

Sourceval pp_value : 'a t -> Format.formatter -> 'a -> unit

pp_value ty fmt vl returns a pretty printer for values of a type ty.

Sourcemodule Numeric : sig ... end

Poor man's type classes for numeric arguments.