Module Webs_html.El

HTML elements and parts.

HTML parts

type html

The type for HTML parts. A part is either a single element or character data or a list of parts.


type name = string

The type for element names.

val v : ?at:At.t list -> name -> html list -> html

v ?at n cs is an element with name n, attributes at (defaults to []) and children cs.

Except for At.class' and the list at must not specify an attribute more than once; this is not checked by the module. For At.class' multiple specifications are gathered to form a single, space separated, attribute value for the class HTML attribute. For multiple specifications are gathered to form a single, semi-colon seperated, attribute value for the style HTML attribute.

See also (and favor) element constructors.


val txt : string -> html

txt d is character data d.

val txt_of : ('a -> string) -> 'a -> html

txt_of f v is txt (f v). Cuts a bit on delimiter orgies.

val sp : html

sp is El.txt " ".

val nbsp : html

nbsp is El.txt "\u{00A0}".


val splice : ?sep:html -> html list -> html

splice ?sep hs when added to a list of children in v splices HTML parts hs into the list, separating each part by sep (if any).

val void : html

void is splice [].

val is_void : html -> bool

is_void h is true iff h is void. This can be either an empty splice, an empty txt or an empty unsafe_raw.

Raw data

val unsafe_raw : string -> html

unsafe_raw s is the raw string s without escaping markup delimiters. s must be well-formed HTML otherwise invalid markup will be generated. This can be used to:

  • Include foreign markup.
  • Avoid unpleasant surprises with the style element.
  • Let user generated content create XSS attacks.


There's more than one way to generate a basic HTML page. The following provides good defaults for a quick minimal document.

val page : ?lang:string -> ?generator:string -> ?styles:string list -> ?scripts:string list -> ?more_head:html -> title:string -> html -> html

page ~lang ~generator ~styles ~scripts ~more_head ~title body is an El.html element with an At.lang attribute of lang (if specified and non-empty) containing a El.head element (see below) followed by body which must be a El.body element.

The other arguments are used to define the children of the page's El.head which are in order:

  1. A charset El.meta of UTF-8 (unconditional).
  2. A generator El.meta of generator, if specified and non-empty.
  3. A viewport El.meta with width=device-width, initial-scale=1 (unconditional).
  4. A stylesheet of type text/css for each element of styles, in order (defaults to []).
  5. A El.script with At.defer and of At.type' text/javascript for each element of scripts, in order (defaults to []).
  6. more_head (defaults to El.void). Be careful with style tags.
  7. The page has a title title which is String.trimed. If the result is empty falls back to "Untitled". See also title_of_filepath.
val title_of_filepath : string -> string

title_of_filepath f is a non-empty page title for filepath f. Either the basename of f without extension or if that results in "index" or "" the basename of the parent directory without extension or if that results in "", "Untitled". Directory separators can be '/' or '\\' regardless of the platform.


val buffer_add : doc_type:bool -> Stdlib.Buffer.t -> html -> unit

buffer_add ~doc_type b h adds HTML part h. If doc_type is true an HTML doctype declaration is prepended.

val to_string : doc_type:bool -> html -> string

to_string is like buffer_add but returns directly a string.

module Low : sig ... end

Low level representation (unstable).

Element constructors

See the MDN HTML element reference.

Convention. Whenever an element name conflicts with an OCaml keyword we prime it, see for example object'.

type cons = ?at:At.t list -> html list -> html

The type for element constructors. This is simply El.v with a pre-applied element name.

type void_cons = ?at:At.t list -> unit -> html

The type for void element constructors. This is simply El.v with a pre-applied element name and without children.

val a : cons
val abbr : cons
val address : cons
val area : void_cons
val article : cons
val aside : cons
val audio : cons
val b : cons
val base : void_cons
val bdi : cons
val bdo : cons
val blockquote : cons
val body : cons
val br : void_cons
val button : cons
val canvas : cons
val caption : cons
val cite : cons
val code : cons
val col : void_cons
val colgroup : cons
val command : cons
val datalist : cons
val dd : cons
val del : cons
val details : cons
val dfn : cons
val div : cons
val dl : cons
val dt : cons
val em : cons
val embed : void_cons
val fieldset : cons
val figcaption : cons
val figure : cons
val form : cons
val h1 : cons
val h2 : cons
val h3 : cons
val h4 : cons
val h5 : cons
val h6 : cons
val head : cons
val header : cons
val hgroup : cons
val hr : void_cons
val html : cons
val i : cons
val iframe : cons
val img : void_cons
val input : void_cons
val ins : cons
val kbd : cons
val keygen : cons
val label : cons
val legend : cons
val li : cons
val main : cons
val map : cons
val mark : cons
val menu : cons
val meta : void_cons
val meter : cons
val nav : cons
val noscript : cons
val object' : cons
val ol : cons
val optgroup : cons
val option : cons
val output : cons
val p : cons
val param : void_cons
val pre : cons
val progress : cons
val q : cons
val rp : cons
val rt : cons
val ruby : cons
val s : cons
val samp : cons
val script : cons
val section : cons
val select : cons
val small : cons
val source : void_cons
val span : cons
val strong : cons
val style : cons


Warning. If your style element holds CSS use unsafe_raw content, otherwise the CSS selector > gets escaped.

val sub : cons
val summary : cons
val sup : cons
val table : cons
val tbody : cons
val td : cons
val textarea : cons
val tfoot : cons
val th : cons
val thead : cons
val time : cons
val title : cons
val tr : cons
val track : void_cons
val u : cons
val ul : cons
val var : cons
val video : cons
val wbr : void_cons