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| author | Kaz Kylheku <kaz@kylheku.com> | 2022-10-04 22:30:36 -0700 |
|---|---|---|
| committer | Kaz Kylheku <kaz@kylheku.com> | 2022-10-04 22:30:36 -0700 |
| commit | bf35c239b435fa34bf3e5b1b286d66ecfbd7ca0a (patch) | |
| tree | e24e8b3ad308a1822c1c0b2d29ccd59255f80b5f /txr.1 | |
| parent | 9c1e2974fad18576c0051d046f03d799d2879fdc (diff) | |
| download | txr-bf35c239b435fa34bf3e5b1b286d66ecfbd7ca0a.tar.gz txr-bf35c239b435fa34bf3e5b1b286d66ecfbd7ca0a.tar.bz2 txr-bf35c239b435fa34bf3e5b1b286d66ecfbd7ca0a.zip | |
oop: allow multiple :init, :fini, etc.
The motivation is that struct clause macros defined
using define-struct-clause may want to introduce
their own initializers and finalizers for the specific
stuff they add to the struct. The uniqueness restrictions
on these initializing and finalizing clauses makes
it impossible to use two clause macros which both want
to inject a definition of the same initializer or finalizer
type.
* stdlib/struct.tl (defstruct): Don't enforce that there
be at most one clause in the category of :init,
:postinit, :fini or :postini. Multiple are allowed.
They all execute left-to-right except for :fini.
* tests/012/fini.tl: New tests.
* tests/012/fini.expected: Updated.
* txr.1: Documented.
Diffstat (limited to 'txr.1')
| -rw-r--r-- | txr.1 | 42 |
1 files changed, 30 insertions, 12 deletions
@@ -29342,11 +29342,12 @@ which the variable .meta param is bound to the structure object. -The +Multiple .code :init -specifier may not appear more than once in a given +specifiers may appear in the same .code defstruct -form. +form. They are executed in their order of appearance, +left to right. When an object with one or more levels of inheritance is instantiated, the @@ -29391,6 +29392,7 @@ of an .code :init specifier are not surrounded by an implicit .codn block . + .meIP (:postinit <> ( param ) << body-form *) The .code :postinit @@ -29419,8 +29421,13 @@ actions, .code :postinit actions registered at different levels of the type's inheritance hierarchy are invoked in the base-to-derived -order, and in right-to-left order among multiple bases -at the same level. +order, in right-to-left order among multiple bases +at the same level. Multiple +.code :postinit +form in the same +.code defstruct +are invoked in left-to-right order. + .meIP (:fini <> ( param ) << body-form *) The .code :fini @@ -29454,9 +29461,11 @@ of a specifier are not surrounded by an implicit .codn block . -At most one +Multiple .code :fini -may be specified. +clauses may be specified in the same +.codn defstruct , +in which case they are invoked in reverse, right-to-left order. Note that an object's finalizers can be called explicitly with .codn call-finalizers . @@ -29464,6 +29473,7 @@ Note: the .code with-objects macro arranges for finalizers to be called on objects when the execution of a scope terminates by any means. + .meIP (:postfini <> ( param ) << body-form *) Like .codn :fini , @@ -29493,17 +29503,25 @@ this omits the parameter, which means that .code :postfini finalizers of derived structures execute after the execution of inherited -finalizers. When both +finalizers. It also means that multiple +.code :postfini +finalizers appearing in the same +.code defstruct +execute in left-to-right order unlike the reverse right-to-left order of +.code :fini +finalizers. + +When both .code :fini and .code :postfini -are specified in the same +clauses are specified in the same .code defstruct -form, the +form, all the .code :postfini -finalizer executes after the +finalizers execute after all the .code :fini -finalizer regardless of the order in which they appear. +finalizers regardless of the order in which they appear. .RE .IP The slot names given in a |