Define an external interface, properly document FIND-OBJC-CLASS.

darcs-hash:2e4424a65b72a13e3cfa26d07dce945bc35ba8e1

1 files changed, 65 insertions, 3 deletions

diff --git a/Lisp/libobjcl.lisp b/Lisp/libobjcl.lisp
index d735773..a7171b4 100644
--- a/Lisp/libobjcl.lisp
+++ b/Lisp/libobjcl.lisp
@@ -7,8 +7,10 @@
 (use-foreign-library libobjcl)
 
 
-(defcfun "objcl_initialise_runtime" :void)
-(defcfun "objcl_shutdown_runtime" :void)
+(defcfun ("objcl_initialise_runtime" initialise-runtime) :void)
+
+(defcfun ("objcl_shutdown_runtime" shutdown-runtime) :void)
+
 (defcfun ("objcl_invoke_instance_method"
           %objcl-invoke-instance-method) obj-data
   (receiver obj-data)
@@ -30,7 +32,67 @@
   (class obj-data))
 
 
-(defun objcl-find-class (class-name)
+(defun symbol->objc-class-name (symbol)
+  (let ((components (split-sequence #\- (symbol-name symbol)
+                                    :remove-empty-subseqs t)))
+    (reduce #'(lambda (x y) (concatenate 'string x y))
+            (mapcar #'(lambda (x)
+                        (concatenate 'string
+                                     (string (char x 0))
+                                     (string-downcase (subseq x 1))))
+                    (subseq components 1))
+            :initial-value (concatenate 'string
+                                        (string (char (first components) 0))
+                                        (string-upcase
+                                         (subseq (first components) 1))))))
+
+
+(defun find-objc-class (class-name)
+  "Retrieve an Objective C class by name.
+
+CLASS-NAME: a symbol or a string.
+
+Returns: an OBJC-CLASS object representing the class whose name is
+CLASS-NAME.
+
+
+If CLASS-NAME is a symbol which does not contain a hyphen, its symbol
+name is converted to lower case except for the first letter, which is
+left intact, and the resulting string used as if directly given as an
+argument to FIND-OBJC-CLASS.
+
+If CLASS-NAME is a symbol which containts a hyphen, its symbol name is
+split into components seperated by hyphens and each component is
+converted into a string according to the following rules:
+
+ 1. The first component is fully converted to upper case except for its
+ first letter, which is left intact.
+
+ 2. Any additional components have all of their letters converted to
+ lower case, except for their first letters, which are left intact.
+
+After this, the components are concatenated in order and the resulting
+string used as if directly given as an argument to FIND-OBJC-CLASS.
+
+Examples:
+
+ (find-objc-class \"NSObject\")   ;=> #<OBJC-CLASS NSObject>
+ (find-objc-class 'ns-object)     ;=> #<OBJC-CLASS NSObject>
+ (find-objc-class 'nsobject)      ;=> NIL
+
+Rationale:
+
+The first component of an Objective C class name is conventionally
+thought of as a namespace identifier.  It is therefore sensible to
+expect it to be converted to upper case by default, which is the
+conventional case for namespace identifiers in Objective C."
+
+  (typecase class-name
+    (string (find-objc-class-by-name class-name))
+    (symbol (find-objc-class-by-name (symbol->objc-class-name class-name)))))
+
+
+(defun find-objc-class-by-name (class-name)
   (let ((obj-data (%objcl-find-class class-name)))
     (prog1
         (if (null-pointer-p (foreign-slot-value