Dear Community,

We are pleased to announce the availability of the Next Scripting
Framework (NSF) 2.3.0. The changes are mostly ... See below for the details.


Diff stats since 2.2.0:
   149 files changed, 15475 insertions(+), 12587 deletions(-)

Major changes relative to 2.2.0 are:

New Features

- NSF:

  * Rename reform for nsf::procs: NSF procedures can now be safely renamed
    (or deleted) using the [rename] command. This was only partially
    supported before, and could also lead to crashes (when redefining
    a renamed nsf::proc).

   * New object property "autonamed": NSF objects having been created
     using "new", rather than using "create", can now be tested for this
     condition using the object property "autonamed":

     % package req nx
     % nsf::object::property [nx::Object new] autonamed
     1
     % nsf::object::property [nx::Object create o] autonamed
     0

     This is to avoid having to rely on pattern sniffing of the
     command names. In addition, the property is now set early enough,
     right after allocating the NSF object, to test for the autonaming
     condition from within the creation procedure (ttrace).
     
   * Extended object property "volatile": By setting or unsetting the
     object property "volatile", a given NSF object can now be
     rendered volatile or not (in addition to using the volatile
     method on the object).

   * Reform of uplevel and upvar: First, uplevel and upvar methods, as
     well as [current callinglevel] and [self callinglevel] now
     behave consistently (re frame skipping for mixin and filter
     transparency). If there is no innermost enclosing proc frame,
     the innermost non-proc (e.g., namespace) frame is selected
     (rather than a "#0" as a default). Second, argument handling for
     both uplevel (i.e., level sniffing in multi-arg case) and
     upvar (e.g., made silent TCL_ERROR for invalid argument
     arities explicit) have been fixed.

- NX:

  * Properties and variables now provide "exists" as an additional
    accessor method, in addition to "get":

    % package req nx
    2.3
    % nx::Class create C {
       :property -accessor public {a 1} 
    }
    ::C
    % ::C create ::c1
    ::c1
    % if {[::c1 a exists]} { ::c1 a get } else { ::c1 a set "1" }
                  ^^^^^^

    This is mainly to provide for symmetry in the property and
    variable API, which otherwise requires one to resort to low-level
    tests for existence, e.g.:

    if {[::c1 eval {info exists :a}]} ...

    This breaks the property/ variable abstraction, because one cannot
    move to a different value store other than object variables w/o
    rewriting client code.

  * Method combination for ensemble methods: Using [next] at the end
    of chains of ensemble methods fired the unknown handler,
    unintentionally. This was fixed.
  * nx::zip rewrite: nx::zip now uses the built-in Tcl 8.6 encode and
    decode facilties, if available, rather than requiring the Trf
    package to be present.

- XOTcl:

  * Improved compatibility of XOTcl2 with XOTcl1 behavior
    for volatile objects (see "volatile reform" above).
  * Improved compatibility of XOTcl2 with XOTcl1 behavior for
    uplevel/upvar from within methods (see "uplevel/ upvar reform"
    above).

- nx::serializer:

  * Improved backward compatibility: Preserve overriding accessor/
    mutators methods (instprocs) for slots.

- MongoDB:

  * Added JSON serializer: The "find all" and "bson" methods now
    provide for JSON-formatted results, on request.

    ::nx::mongo::Class "find all" -asJSON
    ::nx::mongo::Object bson asJSON

  accept the
  -asJSON flag to return a JSON formatted string. This is to
  facilitate implementing single-page JavaScript applications.

- Documentation:

  * Added documentation of uplevel and upvar methods.

- Maintenance & bug fixes:

  * VLA reform: Avoid the use of variable-length arrays (VLA) when
    building argument vectors of Tcl_Objs internally to NSF. Use
    fixed-sized ones (stack-allocated for a size known at compile time
    or dynamically allocated above) to prevent from potential
    overflows and to produce more time-efficient instructions.

  * Tcl 8.7:

    Support for Tcl 8.7a1 and the upcoming, unreleased Tcl 8.7a2
    (core.tcl-lang.org/tcl branch "core-8-branch"). NSF compiles and its
    regression tests execute successfully.

  * Misc (esp. NSF/C): Ran valgrind checks, plugged one source of
    potential leaks (NsfProcStubDeleteProc) and one invalid read on a
    dangling pointer (NsfCCreateMethod).

  * Test suite: Fix recursion tests on 8.5 (windows-only,
    forward.test) for platform-specific error messages (CheckCStack),
    obsolete for 8.6 with NRE. Guarded test case on recursive
    forwards, to avoid preemptive crashes on stack-size limited
    systems.

- Build environments:

  * Turned off COMDAT folding (/opt:icf) under nmake builds which can
    lead to unusable, pointless function-pointer comparisons
    (Nsf_ConvertToSwitch vs.  Nsf_ConvertToBoolean).

  * Improve robustness of configure/ make procedure in the absence of
    generated DTRACE artifacts so that they are truly conditional
    on the corresponding configure flags for DTRACE.

  * Improved robustness of Windows (nmake) installation routines by
    testing for the existence of the install directory.

  * Rendered inference of GIT commit in autotools setup more robust, in
    light of partial GIT checkouts (e.g., w/o tags).

The detailed changelog is available at
https://next-scripting.org/xowiki/download/file/ChangeLog-2.2.0-2.3.0.log

The Next Scripting Framework 2.3.0 (containing NX 2.3.0 and XOTcl
2.3.0) can be obtained from https://next-scripting.org/. Please report
issues and wishes by opening a ticket at
https://sourceforge.net/p/next-scripting/tickets/.

Best regards
- Gustaf Neumann
- Stefan Sobernig