besport / ocaml-googlemaps Goto Github PK

#GoogleMaps binding for OCaml

Dependencies :

To be able to compile and run correctly this binding, you need to install the following packages in opam :

js_of_ocaml

gen_js_api

Installation :

To install it via opam use the folowing commands :

opam pin add ocaml-googlemaps https://github.com/besport/ocaml-googlemaps.git
opam install ocaml-googlemaps

Usage :

A minimal example can be found in the folder example. You only need to type make in the example folder to get example.js, open index.html to see the result

Compilation :

First, compile your source code into ocaml bytecode :

ocamlfind ocamlc -o example.byte -no-check-prims -package js_of_ocaml,gen_js_api,ocaml-googlemaps -linkpkg example.ml

Then you can get a js file from your bytecode thanks to js_of_ocaml :

js_of_ocaml -o example.js +gen_js_api/ojs_runtime.js example.byte

Documentation and conventions used :

You can find the official documentation: https://developers.google.com/maps/documentation/javascript/3.24/reference

The conventions used are gen_js_api 's :

• An upper X letter becomes _x
• Javascript new MyClass becomes MyClass.new_my_class
• Javascript records ("Object" in Google Maps API documentation) become a module containing function :
  • create : which creates the object. Its parameters are all labelled by fields name
  • foofield : a getter for the field called foofield
  • set_foofield : a setter for the field called foofield

WARNING : Some objects in Google Map API contain a field called type. As type is a keyword in OCaml, you need to use type'

Example in Javascript :

var opts = 
  {
    center: {lat: -34.397, lng: 150.644},
    zoom: 10
  };
opts.zoom = 8;
var map = new google.maps.Map(document.getElementById('map'), opts);

Becomes in OCaml (supposing map is the Dom element where to place the map) :

open Googlemaps
let position = LatLng.new_lat_lng (-34.397) 150.644 in
let opts = MapOptions.create ~center:position ~zoom:10 () in
let () = MapOptions.set_zoom opts 8 in
let map = Map.new_map maps opts ()

Here, as the last arguments of create and new_map are optional, we also need to give ()

Version used :

This binding is using Google Map v3.24

Known bugs:

• The namespace Dataisn't done yet