JSON.Pointer

implements RFC 6901 JSON Pointer, addressing a value inside a JSON document with a string such as /foo/0/bar.

array-index

defn

(Fn [(Ref String a)] (Maybe Int)) 

                        (array-index s)

parses a reference token as an array index.

Returns Nothing unless the token is 0 or a positive integer without a leading zero, per RFC 6901. The end-of-array token - is not an index and also yields Nothing.

escape

defn

(Fn [(Ref String a)] String) 

                        (escape s)

encodes a single reference token, turning ~ into ~0 and / into ~1 so it can be embedded in a pointer string.

get

defn

(Fn [(Ref JSON a), (Ref String b)] (Maybe JSON)) 

                        (get doc pointer)

resolves an RFC 6901 JSON Pointer against doc, returning a copy of the addressed value or Nothing. The empty pointer addresses the whole document; array tokens follow array-index.

(JSON.Pointer.get &doc "/foo/0")

parse

defn

(Fn [(Ref String a)] (Maybe (Array String))) 

                        (parse p)

parses a pointer string into its decoded reference tokens.

The empty string yields an empty token array, addressing the whole document. A non-empty pointer must begin with / or Nothing is returned. Empty tokens are preserved, so a trailing / addresses the empty-string key.

unescape

defn

(Fn [(Ref String a)] String) 

                        (unescape s)

decodes a single reference token, turning ~1 back into / and ~0 back into ~ in a single left-to-right pass, per RFC 6901.