Dict (melange.Js.Dict)

type t('a) = Js.dict('a);

Dictionary type (ie an '{ }' JS object). However it is restricted to hold a single type; therefore values must have the same type.

This Dictionary type is mostly used with the Js_json.t type.

type key = string;

Key type

let get: t('a) => key => option('a);

get dict key returns None if the key is not found in the dictionary, Some value otherwise

let unsafeGet: t('a) => key => 'a;

unsafeGet dict key return the value if the key exists, otherwise an undefined value is returned. Must be used only when the existence of a key is certain. (i.e. when having called keys function previously.

Array.iter (fun key -> Js.log (Js_dict.unsafeGet dic key)) (Js_dict.keys dict)

let set: t('a) => key => 'a => unit;

set dict key value sets the key/value in dict

let keys: t('a) => array(string);

keys dict returns all the keys in the dictionary dict

let empty: unit => t('a);

empty () returns an empty dictionary

let unsafeDeleteKey: Js.Fn.arity2((t(string) => string => unit));

Experimental internal function

let entries: t('a) => array((key, 'a));

entries dict returns the key value pairs in dict (ES2017)

let values: t('a) => array('a);

values dict returns the values in dict (ES2017)

let fromList: list((key, 'a)) => t('a);

fromList entries creates a new dictionary containing each (key, value) pair in entries

let fromArray: array((key, 'a)) => t('a);

fromArray entries creates a new dictionary containing each (key, value) pair in entries

let map: f:Js.Fn.arity1(('a => 'b)) => t('a) => t('b);

map f dict maps dict to a new dictionary with the same keys, using f to map each value