The JSON_STREAM_OUTPUT signature

The JSON_STREAM_OUTPUT signature defines an interface for stream-output of JSON values.

Synopsis

signature JSON_STREAM_OUTPUT

structure JSONBufferPrinter : JSON_STREAM_OUTPUT
    where type outstream = CharBuffer.buf
structure JSONStreamPrinter : JSON_STREAM_OUTPUT
    where type outstream = outstream

Interface

type outstream

type printer

val new : outstream -> printer
val new' : {strm : outstream, pretty : bool} -> printer

val close : printer -> unit

val null : printer -> unit
val boolean : printer * bool -> unit
val integer : printer * IntInf.int -> unit
val int : printer * int -> unit
val float : printer * real -> unit
val string : printer * string -> unit
val beginObject : printer -> unit
val objectKey : printer * string -> unit
val endObject : printer -> unit
val beginArray : printer -> unit
val endArray : printer -> unit

val value : printer * JSON.value -> unit

Description

type outstream: The type of the text consumer that the printer is layered on top of.
type printer: The printer type tracks the current state of the output so that it can correctly add punctuation and white space (when pretty printing).
val new : outstream -> printer: new outS creates a new printer from the output stream outS. The printer produces a condensed format without newlines or indentation; use the new' function to create a pretty-printer for JSON output.
val new' : {strm : outstream, pretty : bool} -> printer: new' {strm, pretty} creates a new pretty-printing stream from the output stream strm, where the value of the pretty field controls whether the output is condensed (when pretty is false) or printed with new lines and indentation to improve readability (when pretty is true).
val close : printer -> unit: close pr closes the printer, but not the underlying output stream. Closing the printer while there is an open object or array results in the Fail exception being raised. Also, calling any of the below printing functions on a closed printer will result in the Fail exception being raised.
val null : printer -> unit: null pr prints the JSON null value. Raises the Fail exception if the printer is closed.
val boolean : printer * bool -> unit: boolean (pr, b) prints the JSON boolean value b. Raises the Fail exception if the printer is closed.
val integer : printer * IntInf.int -> unit: integer (pr, n) prints the JSON number n. Raises the Fail exception if the printer is closed.
val int : printer * int -> unit: int (pr, n) prints the JSON number n. Raises the Fail exception if the printer is closed. This function is a convenience for when one wants to print a default-int-type value without converting it to a IntInf.int first.
val float : printer * real -> unit: float (pr, r) prints the JSON floating-point number r. Raises the Fail exception if the printer is closed.
val string : printer * string -> unit: string (pr, s) prints the JSON string s. Raises the Fail exception if the printer is closed.
val beginObject : printer -> unit: beginArray pr prints the opening “{” for a JSON object. Note that each call to beginObject should be matched by a call to endObject. Raises the Fail exception if the printer is closed.
val objectKey : printer * string -> unit: objectKey (pr, key) prints the JSON key-value key followed by a “:”. This function should be inside matched beginObject/endObject calls and should be followed by the printing of a JSON value. Raises the Fail exception if the printer is closed.
val endObject : printer -> unit: endObject pr prints the closing } for the currently open object. The Fail exception is raised if the current context is not an open object, if a key has been printed without an associated value, or if the printer is closed.
val beginArray : printer -> unit: beginArray pr prints the opening “[” for a JSON array. Note that each call to beginArray should be matched by a call to endArray. Raises the Fail exception if the printer is closed.
val endArray : printer -> unit: endArray pr prints the closing ] for the currently open array. The Fail exception is raised if the current context is not an open array or if the printer is closed.
val value : printer * JSON.value -> unit: value (pr, v) embeds the JSON value v in the output. It is equivalent to recursively traversing the JSON value while calling the appropriate output functions from above.

Synopsis

Interface

Description

See Also