Encodes characters that need protection by converting them to * entity references. E.g. "<" is converted to "<". * As the entities may be named, there is a dependency on the character * set.
val encode :
in_enc:Netconversion.encoding ->
?out_enc:Netconversion.encoding ->
?prefer_name:bool ->
?unsafe_chars:string ->
unit ->
string ->
stringThe input string that is encoded as in_enc is recoded to * out_enc, and the following characters are encoded as HTML * entity (&name; or &#num;): * - The ASCII characters contained in unsafe_chars * - The characters that cannot be represented in out_enc. By * default (out_enc=`Enc_usascii), only ASCII characters can be * represented, and thus all code points >= 128 are encoded as * HTML entities. If you pass out_enc=`Enc_utf8, all characters * can be represented. * * For example, the string "(a<b) & (c>d)" is encoded as * "(a<b) & (c>d)". * * It is required that out_enc is an ASCII-compatible encoding. * * The option prefer_name selects whether named entities (e.g. <) * or numeric entities (e.g. <) are prefered. * * The efficiency of the function can be improved when the same encoding * is applied to several strings. Create a specialized encoding function * by passing all arguments up to the unit argument, and apply this * function several times. For example: *
* let my_enc = encode ~in_enc:`Enc_utf8 () in
* let s1' = my_enc s1 in
* let s2' = my_enc s2 in ...
* val decode :
in_enc:Netconversion.encoding ->
out_enc:Netconversion.encoding ->
?lookup:(string -> string) ->
?subst:(int -> string) ->
?entity_base:entity_set ->
unit ->
string ->
stringThe input string is recoded from in_enc to out_enc, and HTML * entities (&name; or &#num;) are resolved. The input encoding * in_enc must be ASCII-compatible. * * By default, the function knows all entities defined for HTML 4 (this * can be changed using entity_base, see below). If other * entities occur, the function lookup is called and the name of * the entity is passed as input string to the function. It is * expected that lookup returns the value of the entity, and that this * value is already encoded as out_enc. * By default, lookup raises a Failure exception. * * If a character cannot be represented in the output encoding, * the function subst is called. subst must return a substitute * string for the character. * By default, subst raises a Failure exception. * * The option entity_base determines which set of entities are * considered as the known entities that can be decoded without * help by the lookup function: `Html selects all entities defined * for HTML 4, `Xml selects only <, >, &, ", * and ', * and `Empty selects the empty set (i.e. lookup is always called).