Things WikiTalk can't do

These are things that there appears to be no possible way to do in WikiTalk.

• Validate, convert and fix dates
• Sort an array in descending order
• Reuse variables
• Merge multiple topics' content into one page
• Put comments in code
• Handle errors
• Handle international characters for ex. Norwegian æ, ø and å

Fixed but not released:

Features released:

• Remove duplicate values from an array
• Add, subtract, multiply and divide integers

Validate, convert and fix dates

Examples and/or test cases:

• Given today's date, loop through the mondays for the past four weeks.
• Find invalid topic property values containing dates. Example: Users create topics with a date property such as Reportdate. Users may enter in "yyyy-mm-dd", "yyyymmdd" or "m/d/y" format. I should be able to create a topic that gives me the list of all topics with incorrect dates or date formats. (e.g. Date.DateValue(theproperty, "yyyy-mm-dd") or Date.IsValid(theproperty, "m/d/yyyy") Note: Locality matters for date formats. Think January 2nd, 2003. US is 1/2/3 or 1/2/03. UK is 2/1/03. ymd is 3/1/2. Can also use dashes instead of slashes.

Sort an array in descending order

You can sort an array but you can't sort it descending. For example, a set of topics have a property ReportDate which is in yyyy-mm-dd format. I want the most recent reports listed first.

Examples and/or test cases:

• Sort the array ["a", "b", "c"] so it returns "cba".

• I have added a Reverse function to FlexWikiEngine.BELArray.cs for that. I am currently finding out how to get write access to the CVS. In the meantime, maybe you can add it manually yourself? -- HansB

                [ExposedMethod(ExposedMethodFlags.CachePolicyNone, "Reverse the array")]
                public BELArray Reverse()
                {
                        ArrayList answer = new ArrayList(Array);
                        answer.Reverse();
                        return new BELArray(answer);
                }

Reuse variables

Variables are not supported in WikiTalk. This is key to performance. For example, a complex search across thousands of topics might result in 10 topics being found.

Examples and/or test cases:

• A complex search across thousands of topics might result in 10 topics being found. You want to list the topics at the top of the page and then summarize them later in the page.
• Search across thousands of topics and give the count for how many topics are found. Then go back and list the topics without having to pass the results array to a function (topic property function).

Merge multiple topics' content into one page

There is no way to use WikiTalk to insert a topic's content into the another topic.

Examples and/or test cases:

• Status reports are entered as individual topics. Sample code to get all status reports: namespace.TopicsWith("ISTopicType", "StatusReport").Sort Test case is to generate a consolidated status report.

Comment

Can't you do this using the _Body property? That is, something like this

        @@namespace.TopicsWith("TestPropertyForThisPage", "test").Collect{e|e.GetProperty("_Body")}@@

However, don't put that property on the same page as the WikiTalk code that queries for it, or you can create an infinite recursion situation!

-- JimmySieben [2005-09-08]

Put comments in code

Yes, you cannot comment your code. However, you can use this bogus method...

 AFunction:{
    "This is my comment".Substring(0, 0),
    ... code here ...
 }

...or use the slightly cleaner bogus hidden property method...

 :XX: My function summary here.
 AFunction:{
    ... code here ...
 }

...of course you can replace XX with any valid WikiPageProperty name.

Examples and/or test cases:

• Take any WikiTalk function of 10 lines or more and document what each line does.

Handle errors

There is some ability to handle errors but it is complex and requires duplicating code or breaking the code into many functions.

Examples and/or test cases:

• Take a long function and error trap ToOneString.SubString(10, 1).Equals("x").IfTrueIfFalse... when the string is less than 10 characters.

Things you can do with WikiTalk but are very difficult

Fixed but not released

Features released

Remove duplicate values from an array

Feature request 1104399 Implemented in 1642. See ChangeNoteForUniqueValuesInArrays.

Implemented through Unique method on arrays.

Examples and/or test cases:

• Out of 100 topics, there are 10 unique values in the Reportdate property. List the 10.
• The Recent Topics list (right hand side of screen) includes duplicate names. Change to show the 10 most recent topics names, ordered by when I last visited them.

I can think of two (for now) approaches to this that we could take:

1. Provide a Unique method to the ArrayType that returns another Array containing just the unique entires.
2. Implement a Hashtable-like type that can only hold unique values from the outset.

The Unique method approach would undoubtedly be quicker to implement, but I don't see either as being particularly arduous -- DerekLakin [18-Jan-2005]

Note that there is already a Set class inside FlexWiki that does exactly this. It could be exposed in WikiTalk. Of course, that starts to open the door to questions about a whole class hierarchy for collections (<picture of David running screaming away as fast as possible...>. Adding a single Unique method to Array is probably a nice start. -- DavidOrnstein [18-Jan-2005]

Add, subtract, multiply and divide integers

Feature request 1104401 implemented in version 1642. See ChangeNoteForIntegerArithmetic.

Examples and/or test cases:

• Create a table listing projects, their costs and the total. Projects would be individual topics with each topic having Projectcost attribute containing the cost.

Like most problems there are several possibilities for solving this too:

1. Implement the required operators in WikiTalk so that '+', '-', '*' and '/' can be used in WikiTalk. This could be applied, where appropriate, for other types.
2. Implement a Math class that provides Add, Subtract, Multiply and Divide methods. These methods could accept (and return) ObjectTypes allowing the operations on other types (where appropriate).
3. Implement Add, Subtract, Multiply and Divide methods on the IntegerType.

Providing operator support in WikiTalk itself would be longer and more complicated (I suspect) than any other approach. Implementing a Math class would be a good way of centralising all the arithmetic functionality. Adding the relevant methods to the Integer class would be consistent with the approach taken in existing classes such as the DateTimeType.

That's not to say that the existing arithmetic methods in existing classes couldn't be moved out to a new Math class, but it would be a breaking change.

I'm happy to take either/both of these on once we've had a discussion and resolved upon which approach to take. -- DerekLakin [18-Jan-2005]

There has been discussion about the introduction of operators and it would be nice for them to come along at some point. There's a topic on it, but I can't find it right now. I think the way this was envisioned was that the actual infix notation with a binary operator (like 1+2) really translated into calls to the appropriate methods on the object on the left (in this case calling Plus() on Integer), passing in the second integer.

I think if you went ahead and added a few math functions to Integer, that might work nicely for now -- before we get the nicer syntax. And would blend well with the imagined implementation strategy for binary operators in the future. -- DavidOrnstein [18-Jan-2005]