v0.22.0

MINOR: before 1.0.0, a breaking change increases MINOR. A deep recursion through closures gives #DEPTH! at a lower depth than before. No export goes.

Changes of behavior

• A clock for call gives one #DEPTH! in each tier (D125). Each application of a closure of fn counts one level. An application by call and an application by an operation of the host both count. The clock permits ceil(maxDepth / 4) levels, thus 250 for the default maxDepth of 1000.
  • In 0.21.0, an endless recursion stopped at the stack of the host. It gave #DEPTH! with a RangeError as its cause, at a place that changed with the tier.
  • In 0.22.0, it gives #DEPTH! with the reason "The applications of functions nest deeper than 250 levels." The document that applies the closure gets the place, in each tier.
  • The break: a finite recursion of 251 to approximately 1600 nested applications gave its value in 0.21.0. In 0.22.0, it gives #DEPTH!. A host that needs a deeper recursion sets a larger maxDepth.
  • The limit comes from one measure. On Node.js 24.21.0 on Windows, the reference tier overflowed the stack of the host after 937 applications, and the plan after 1595.
  • The test FORMULA.CALL-DEPTH runs the reference at twice the default limit with no RangeError. Thus a Node.js version with a smaller stack fails that test in CI first.

New features

• Attributes with parameters (D124). The new table tree.at of a tree contract gives an attribute with parameters an entry { params, equation }. The new standard step tree.at with the fields attr and args reads an instance of the node. For example, a parent asks for the height of a child at a given width.
  • The equation sees each parameter as a name, for example names.width. A missing or an extra argument gives #VALUE!.
  • Two arguments share one memo entry only when they are equal by DOC.EQUALS. A host with cells gets one cell for each instance.
  • check examines each entry and each step with literal arguments. The graph of attribute instances gives an exact vertex for such a step, with the new field args.
  • An entry cannot be circular or collect. The text syntax has no form for args, thus a step with arguments is a document.
  • The new exports are AtArgs, AtEquation, AtRule, argsKey, atArgsOf and atRuleOf.