Changeset 1720

Timestamp:

11/01/08 19:18:27 (2 months ago)

Author:

Chuck.Esterbrook

Message:

Added a shortcut syntax for declaring a property and its backing variable in one line.
ticket:46
reported-by:necromanco

Location:

cobra/trunk

Files:

• Developer/IntermediateReleaseNotes.text (modified) (1 diff)
• Source/CobraParser.cobra (modified) (1 diff)
• Tests/120-classes/504-properties-from.cobra (modified) (2 diffs)

cobra/trunk/Developer/IntermediateReleaseNotes.text

@@ -9 +9 @@
 
 * Added new install-from-workspace command in the Source directory. This makes installing out of a Subversion workspace very easy and reliable. Documentation is in the doc string at the top of InstallFromWorkspace.cobra.
+
+* Added a shortcut syntax for declaring a property and its backing variable in one line:
+.code
+        get x from var as int
+        # is a short cut for these two lines:
+        var _x as int
+        get x from var
+
+        # the general form of the shortcut above is:
+        get <name> from var as <type>
+        
+        # the fully general form is:
+        (get|pro|set) <name> from (var|<varName>) as <type>
 
 * Modified commandline options so -r becomes synonym for -run rather  

cobra/trunk/Source/CobraParser.cobra

@@ -1533 +1533 @@
                 else
                         varName = .expect('ID').text
-                possibleVarDef = .curBox.declForName(varName)
-                if possibleVarDef is nil
-                        .throwError('There is no variable named "[varName]" to match the property "[name]".')
-                if not possibleVarDef inherits BoxVar
-                        .throwError('A property can only cover for variables. [varName] is a [possibleVarDef]')
-                varDef = possibleVarDef to BoxVar
+                declVarType = if(.optional('AS'), .typeId, nil)
+                if declVarType
+                        varDef = BoxVar(token, .curBox, varName, declVarType, List<of String>(_isNamesStack), nil, nil, 'Automatic backing var for property "[name]".')
+                        .curBox.addDecl(varDef)
+                else
+                        possibleVarDef = .curBox.declForName(varName)
+                        if possibleVarDef is nil
+                                .throwError('There is no variable named "[varName]" to match the property "[name]".')
+                        if possibleVarDef inherits BoxVar
+                                varDef = possibleVarDef
+                        else
+                                .throwError('A property can only cover for variables. [varName] is a [possibleVarDef]')  # TODO: .englishName?
                 if .curBox inherits Interface
                         .throwError('Cannot use the "from" form of a property inside an interface declaration.')

cobra/trunk/Tests/120-classes/504-properties-from.cobra

@@ -23 +23 @@
                 """
 
-        def main is shared
-                p as Person = Person()
-                p.ageProp = 5
-                assert p.age==5
-                p.age1 = 6
-                assert p.age1==6
-                p.age2 = 7
-                assert p.age3==7
-                p.age = 8
-                assert p.age==8
+        shared
+
+                def main
+                        .testPerson
+                        .testPoint
+        
+                def testPerson
+                        p as Person = Person()
+                        p.ageProp = 5
+                        assert p.age==5
+                        p.age1 = 6
+                        assert p.age1==6
+                        p.age2 = 7
+                        assert p.age3==7
+                        p.age = 8
+                        assert p.age==8
+        
+                def testPoint
+                        p as Point = Point()
+                        assert p.x == 0 and p.y == 0
+                        p.moveBy(2, 3)
+                        assert p.x == 2 and p.y == 3
 
 
@@ -61 +73 @@
         get foo from var
                 is override
+
+
+class Point
+
+        # TODO: cover `pro` and `set`
+        # TODO: verify _x is protected and __y is private
+
+        def init
+                _x = 0
+                __y = 0
+
+        get x from var as int   # typical property with matching var backing
+        
+        get y from __y as int   # test explicit naming of the var. note that __y will be private
+
+        def moveBy(dx as int, dy as int)
+                _x += dx
+                __y += dy