Changes between Initial Version and Version 1 of PortingC

Timestamp:

10/29/09 12:23:14 (15 years ago)

Author:

hopscc

Comment:

--

PortingC

@@ +1 @@
+= Porting C# code to Cobra =
+
+
+see [wiki:C#Diffs Cobra differences fm C#]
+
+Heres a process for C# to Cobra generally.
+
+
+ 1. Take .cs file, rename to .cobra file.
+
+
+ 2. Change multiline comments from multiple // or /* */ bounded to be /# #/ bounded.[[br]]
+     Change single line comments to use leading ''''#''''
+
+     Remove extraneous separator line comments between method calls - if any  
+        {{{ // ------------------------------ }}}
+        
+ 3. Remove trailing '''';'''' from each line they occur on
+
+ 4.  Fixup blocking and indentation.
+  Remove all '{' and '}' indicating start and end blocks from source.[[br]]
+  Ensure remaining blocks are all correctly (equally) indented and that 
+  indentation uses either all spaces or all Tabs and that the
+  indents are in multiples of either 4 spaces or 1 tab.
+
+     
+ 5. Fix 'using' statements: [[br]]
+    '''using''' -> '''use''' [[br]]
+  Remove any lines for 
+  {{{
+using System
+using System.Collections.Generic
+using System.IO
+using System.Text
+  }}}
+  as cobra includes these automagically
+
+  Change any other lines from 
+        ''''using xxxx;'''' to ''''use xxxx''''                    
+
+
+ 6. Namespace decl
+    Namespaces in cobra need to start with an upcased letter. [[BR]]
+    Remove any lowercased  prefix from namespace line  
+
+
+ 7. Correct any Enum definitions. [[br]]
+    After applying the above its basically removing trailing ',' and ensuring indentation
+    of enum items are all the same.
+    e.g. 
+    {{{
+enum ID_CONTROLS  {
+    ID_RADIO_ORIENT = 5999,
+    ID_CHK_SHOWIMAGES,
+    ID_BTN_NEXT_PAGE,
+    ID_NOTEBOOK
+}
+    }}}
+    to
+    {{{
+enum ID_CONTROLS
+    ID_RADIO_ORIENT = 5999
+    ID_CHK_SHOWIMAGES
+    ID_BTN_NEXT_PAGE
+    ID_NOTEBOOK
+    }}}
+
+
+ 8. Fix class declaration syntax
+      Change lines like ''''class X : Y'''' to ''''class X inherits Y''''        
+
+
+ 9. Change any class instance attributes/fields to be prefixed with ''''var''''
+    Change type and accessmodifier to cobra forms
+   {{{
+<Type> name = <init> ;
+   }}}
+   to 
+   {{{
+var name as <Type> = <init>
+    }}}           
+
+10. Fixup class constructor definitions
+     For initializer/constructor change lines like :
+        {{{ public ClassName(params,...) : base(baseParams,...) }}}
+      to
+{{{
+    cue init(params, ...) is public
+        base.init(baseParams,...) 
+}}}        
+
+     Within the params list correct type declaration syntax from C# to cobra
+     {{{
+[<accessModifier> ...] <Type> name, 
+     }}}
+     to 
+     {{{
+name as <Type> [is <accessModifier>, ...],
+     }}}
+
+     public is default accessModifier so can leave that off[[br]]       
+     e.g.
+    {{{
+public GeoArea (string title, GeoPoint pos, Size size) : base(title, pos, size)
+    }}}
+   to 
+    {{{
+cue init(title as String, pos as GeoPoint, size as Size ) is public
+    base.init (title, pos, size)
+    }}}
+               
+11. Remove any uses of ''''new'''' to construct a class instance, 
+    instead just make a call to the class type passing any initializer args, i.e just remove 'new'[[br]]
+    e.g.
+    {{{
+    new gFile = new GeoFile() -> gFile = GeoFile()
+    new GeoPoint(10, 100)     -> GeoPoint(10, 100)
+    new Size(650,340)         -> Size(650, 340)
+    }}}
+
+    For classes that construct delegates (take method names) prefix the methodname with '''ref''', 
+    methodNames must start with a lowercase letter and are prefixed by ''''this.'''' or just ''''.''''
+    so change the methodName accordingly
+        e.g. {{{new Listener( OnFileChange )  -> Listener(ref .onFileChange) }}}
+
+
+12. Methods:
+    Prefix methods with '''def'''.[[br]]
+    Change methodnames to start with a lowercase letter, [[br]]
+    Change param definitions to cobra form.[[br]]
+        {{{[<accessModifier> ...] <Type> name,}}} -> {{{name as <Type> [is <accessModifier>, ...],}}}
+    Cobra methods by default return void and are public so if the C# code specifies '''public void''' 
+    you can just delete those words.
+
+    Also, if a method has no parameters then the empty trailing () can be left off.
+            
+    Note builtin types:
+        C# string -> String (System.String) [[br]]
+        C# object -> Object (System.Object) [[br]]
+    {{{
+public void OnFileChange( object sender, Event e )
+    }}} 
+   to 
+    {{{
+def onFileChange(sender as Object, e as Event)  
+
+    # no param method
+    public override bool OnInit()
+    }}}
+     ->
+    {{{
+def onInit as bool is override 
+    # or def onInit as bool is public, override # explicit
+}}}
+            
+13. Calls to methods, properties and attributes/fields.
+     Instance method names, properties and fields are called with a prefix of ''''this.'''' or just ''''.'''' [[br]]
+     and they all must be named starting with a lowercase letter so the calls and settings[[br]]
+     must be modified accordingly.
+
+     e.g.
+   {{{
+    gFile.AppendPosn(...   ->   gFile.appendPosn( ...
+    CreateNewCity()       -> .createNewCity # or this.createNewCity
+   }}}
+    Similarly with properties and fields
+   {{{
+    Street = new Street(this, ...   ->  .street = Street(this, ...
+    }}}
+
+    If a method takes no args then any empty trailing () on a method call can/should be left off.
+
+14.  Property definition. Depending on the property use, prefix properties with :[[br]] 
+        * get - readable property only 
+        * set - settable property only
+        * pro - gettable and settable
+
+    Change property names to start with a lowercase letter
+
+
+15. Local variables declared and assigned on first use can usually be changed to remove 
+    the type definition (type inferred from the assignment) or can still be explicitly typed.
+    {{{
+    DataItem info = new DataItem() 
+      ->
+    info = DataItem()     # or    info as DataItem = DataItem()
+    }}}
+    
+
+
+16. Fixup 'For' loops
+    {{{
+for ( <Type> name = start ; name < stop; ++name ) 
+        ->
+for name as Type in start : stop : 1 # explicit or equally use shortcuts:
+for name in start : stop : 1 
+for name  in start : stop  # if step is one (1)
+for name in stop           # if start is zero (0) and step is one (1)
+    # same as for name in 0 : stop : 1
+    }}}
+    
+    e.g {{{ for ( int i = 0; i < 200; ++i ) -> for i in 0 : 200 }}}    
+
+
+17. Casting
+    Casts of form '(Type)name' become 'name to Type' [[BR]]
+    e.g.  {{{ ... (object) cl.MyString ...  -->  ... cl.myString to Object ... }}}
+
+    Casts of form 'a as Type' can also become 'name to Type' or 'name to? Type'
+    e.g {{{ ListEvent le = event as ListEvent;   --->  le = event to ListEvent }}}
+        
+18. String catenated with expressions (converted to string) can be modified to use string interpolation.
+    Put the expressions ( suitably cobra converted) into the string inside []
+    e.g. {{{ "Value " + item.Value + " selected item: " + item.Selected  --->  "Value [item.value] selected item:[item.selected]" }}}
+             
+19. Adding eventHandlers
+    Cobra uses the '''listen''' statement to register event handlers where C# uses an override on 
+    the += operator.  [[br]]
+    Otherwise normal cobra mapping for method names and reference to methods (vs method calls) apply;[[br]]
+    Methodnames in Cobra must start with a lower case letter and calls to this instance names 
+        are prefixed with ''''this.'''' or (easier) ''''.''''
+    
+    When translating from a 'use'd library namespace,  calls to[[br]] 
+        Capcased methodnames are referenced in cobra with the first '''char''' lowercased,[[br]] 
+        Upcased methodnames  are referenced with the first '''word''' lowercased
+    so 
+    {{{
+    EVENT +=  new Listener(MethodName)  in C# becomes
+    listen .EVENT,      Listener( ref .methodName ) 
+
+    EVENT += new Listener( EH_METHOD_NAME ) in C# becomes
+    listen .EVENT,      Listener( ref .eh_METHOD_NAME ) 
+    }}}
+    e.g.
+    {{{
+    FileChange += new Listener( OnFileChange )
+        ->
+    listen .fileChange,    Listener(ref .onFileChange) 
+    }}}
+
+
+20. Main method
+    'public void' is default, static is an accessmodifier which becomes ''''shared'''' in cobra,
+    C# attributes (!MetaInformation) are denoted with ''''has''''
+    e.g.
+    {{{
+[STAThread]
+static public void main()
+    }}}
+    becomes 
+    {{{
+def main is shared has STAThread 
+    }}}    
+