Module Kwvalid

module Kwvalid: sig .. end

Validators

This module provides "objects" that validate strings. A given validator essentially imposes a type upon strings, and accepts or rejects them accordingly; they also carry a text description of the type, which can be used in help and error messages.

Types and Exceptions

type t = {

	`t : string;`	`(*`	description of what this validator considers valid (a noun)	`*)`
	`f : string -> bool;`	`(*`	test function	`*)`

}

The type of validators.

exception Invalid of string * string

Exception rasied by Kwvalid.mustbe and Kwvalid.asserted.

str is an invalid what.

val error : Format.formatter -> string -> string -> unit

val string_of_exn : exn -> string

string_of_exn: convert Kwvalid exceptions to strings describing them.

Calling Validators

Validators are Boolean functions; you can call t.f directly, or use one of these convenience functions.

val valid : t -> string -> bool

valid t str: is str a valid t?

t : the validator

str : the string to be validated

val mustbe : t -> string -> unit

mustbe t str: check that str is a valid t and raise an exception if not.
Raises Invalid if str not a valid t

t : the validator

str : the string to be validated

val asserted : t -> string -> string

asserted t str: check that str is a valid t, raising an exception if not, and return str.
Raises Invalid if str not a valid t

t : the validator

str : the string to be validated

Creating Validators and Primitive Validators

val make : string -> (string -> bool) -> t

make text predicate: make a validator from an arbitrary predicate

val always : t

always considers any argument string valid.

val any : t

any considers any argument string valid.

val never : t

never never considers any argument string valid.

val enum : string list -> t

enum list: considers valid any string in the given list.

module Combinator: sig .. end

Validators

module Number: functor (N : NUMBER) -> sig .. end

Number Validators

module Num: sig .. end

Validators for Predefined Number Domains

module String: sig .. end

String Validators

module B: sig .. end

Boolean Validators 𝔹

module File: sig .. end

File Validators

module Directory: sig .. end

Directory Validators

module Json: sig .. end

Json Validators

Combinators for validators

val warning : Format.formatter -> t -> t

warning v: convert the validator v into one that always succeeds, but generates a warning on the formatter fmt if the validation fails.

fmt : the formatter

v : the validator

val not : t -> t

not v: negate the return value of a validator.

E.g. not File.existing is a validator that insists on a non-existent file.

val (&&) : t -> t -> t

a && b: conjunction of two validators.

val (||) : t -> t -> t

a || b: disjunction of two validators.