Document alien.destructors

basis/alien/c-types/c-types-docs.factor

@@ -217,6 +217,8 @@ $nl
 "Utilities for automatically freeing memory in conjunction with " { $link with-destructors } ":"
 { $subsection &free }
 { $subsection |free }
+"The " { $link &free } " and " { $link |free } " words are generated using " { $link "alien.destructors" } "."
+$nl
 "You can unsafely copy a range of bytes from one memory location to another:"
 { $subsection memcpy }
 "You can copy a range of bytes from memory into a byte array:"
@@ -243,4 +245,6 @@ $nl
 "New C types can be defined:"
 { $subsection "c-structs" }
 { $subsection "c-unions" }
+"A utility for defining " { $link "destructors" } " for deallocating memory:"
+{ $subsection "alien.destructors" }
 { $see-also "aliens" } ;

basis/alien/destructors/destructors-docs.factor

@@ -0,0 +1,30 @@
+IN: alien.destructors
+USING: help.markup help.syntax alien destructors ;
+
+HELP: DESTRUCTOR:
+{ $syntax "DESTRUCTOR: word" }
+{ $description "Defines four things:"
+  { $list
+    { "a tuple named " { $snippet "word" } " with a single slot holding a " { $link c-ptr } }
+    { "a " { $link dispose } " method on the tuple which calls " { $snippet "word" } " with the " { $link c-ptr } }
+    { "a pair of words, " { $snippet "&word" } " and " { $snippet "|word" } ", which call " { $link &dispose } " and " { $link |dispose } " with a new instance of the tuple" }
+  }
+  "The " { $snippet "word" } " must be defined in the current vocabulary, and must have stack effect " { $snippet "( c-ptr -- )" } "."
+}
+{ $examples
+  "Suppose you are writing a binding to the GLib library, which as a " { $snippet "g_object_unref" } " function. Then you can define the function and destructor like so,"
+  { $code
+    "FUNCTION: void g_object_unref ( gpointer object ) ;"
+    "DESTRUCTOR: g_object_unref"
+  }
+  "Now, memory management becomes easier:"
+  { $code
+    "[ g_new_foo &g_object_unref ... ] with-destructors"
+  }
+} ;
+
+ARTICLE: "alien.destructors" "Alien destructors"
+"The " { $vocab-link "alien.destructors" } " vocabulary defines a utility parsing word for defining new disposable classes."
+{ $subsection POSTPONE: DESTRUCTOR: } ;
+
+ABOUT: "alien.destructors"