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JSONFile

Base class: Object

Represents a lazily loaded JSON document with explicit persistence.

value() returns detached data; set_value() and clear() change memory only. save() and save_as() persist changes. Selection uses RFC 6901 JSON Pointer, such as /samples/0; an empty pointer selects the root. Invalid pointers and missing locations throw. Typed reads accept native primitives or parsed strings.

Example​

var file = JSONFile("results", "w")
file.set_value(["samples": [1.5, 2.5]]).save()
var values = file.value("/samples", as_list | as_real)

Constructors​

JSONFile(const string path) -> JSONFile​

Prepares a JSON document in append/update mode; missing files start with null.

Parameters​

  • path: Relative data-service path; .json is added when no extension exists.

JSONFile(const string path, const string mode) -> JSONFile​

Prepares a JSON document. Modes are r, r+, w, w-/x, and a (default), without regard to case. Create modes start fresh and reload is available only in r/r+/a.

Parameters​

  • path: Relative data-service path.
  • mode: File mode; an empty string uses a.

JSONFile(const string path, const string mode, const Map options) -> JSONFile​

Prepares a JSON document with immutable serialization options.

Parameters​

  • path: Relative data-service path.
  • mode: File mode.
  • options: Boolean pretty (default true): two-space indentation or compact JSON; no final newline.

Members​

NameDescription
clearResets the in-memory value to null without touching the file.
pathReturns the resolved JSON path.
reloadDiscards changes and reloads in r/r+/a modes; failures preserve the previous value.
saveAtomically persists the current value to the local file.
save_asAtomically saves to a new local path and makes it current after success.
set_valueValidates and replaces the entire in-memory value without reading old contents. Registered modules also support nested numeric containers. Mutations require a writable mode.
valueReturns a JSON Pointer-selected value as an array or matrix with logical rows (flat inputs are row vectors). Complex elements use strings.