diff options
| -rw-r--r-- | Lisp/data-types.lisp | 22 | ||||
| -rw-r--r-- | Lisp/method-invocation.lisp | 15 |
2 files changed, 35 insertions, 2 deletions
diff --git a/Lisp/data-types.lisp b/Lisp/data-types.lisp index bd2fae4..a5ec1ba 100644 --- a/Lisp/data-types.lisp +++ b/Lisp/data-types.lisp @@ -54,12 +54,30 @@ ## Description: Method selectors are Objective-C's equivalent to what Common Lisp calls -**symbols**. Their use is restricted to retrieving methods by name. +**symbols**. Their use, however, is restricted to retrieving methods by +name. + +In Common Lisp, you can **funcall** a __selector__ directly (see the +note below for details and why you may want to do this). __selector__ objects cannot be created by means of __make-instance__. Use __find-selector__ instead. +## Note: + +Instead of using __invoke__, which is neither macro-friendly nor very +useful for method selection at run-time, you may **funcall** selectors +directly. Naturally, __apply__ works as well. + +The following calls are all equivalent: + + (invoke-by-name instance \"stringWithCString:encoding:\" \"Mulk.\" 4) + (invoke instance :string-with-c-string \"Mulk.\" :encoding 4) + (funcall (selector \"stringWithCString:encoding:\") instance \"Mulk.\" 4) + (apply (selector \"stringWithCString:encoding:\") (list instance \"Mulk.\" 4)) + + ## See also: __find-selector__")) @@ -77,7 +95,7 @@ Use __find-selector__ instead. (apply #'invoke-by-name receiver selector args)))) -(defclass id (c-pointer-wrapper) () +(defclass id (c-pointer-wrapper) () (:documentation "An instance of an Objective-C class. ## Description: diff --git a/Lisp/method-invocation.lisp b/Lisp/method-invocation.lisp index c0bad01..9aae94d 100644 --- a/Lisp/method-invocation.lisp +++ b/Lisp/method-invocation.lisp @@ -108,6 +108,20 @@ separating parts by hyphens works nicely in all of the `:INVERT`, *modern mode*. +## Note 2: + +Instead of using __invoke__, which is neither macro-friendly nor very +useful for method selection at run-time, you may **funcall** selectors +directly. Naturally, __apply__ works as well. + +The following calls are all equivalent: + + (invoke-by-name instance \"stringWithCString:encoding:\" \"Mulk.\" 4) + (invoke instance :string-with-c-string \"Mulk.\" :encoding 4) + (funcall (selector \"stringWithCString:encoding:\") instance \"Mulk.\" 4) + (apply (selector \"stringWithCString:encoding:\") (list instance \"Mulk.\" 4)) + + ## See also: __invoke-by-name__" @@ -168,6 +182,7 @@ are all equivalent: In fact, using __invoke-by-name__ is discouraged in favour of the latter form. + ## Rationale: Whereas __invoke__ tries to make writing as well as reading method |