Linq brings back lisp memories

Often when I am searching for the most succinct way to write logic, I find myself using a declarative syntax:

public  ExecutionOutcome GetValidationMessages()
       {
           IEnumerable<ExecutionOutcome> failedExecutionOutcomes = Context.ItemGroups
               .Where(x=>x.IsValid==false)
               .Select(x=>ExecutionOutcome.CreateFailureOutcome(
                       string.Format(
                                                        "...",
                                                        x.ItemGroupName
                       )
                   )  
               );
           if(failedExecutionOutcomes.Count()>0)
           {
               return ExecutionOutcome.CreateFailureOutcome(failedExecutionOutcomes.Aggregate(string.Empty, (x,y) => x += y.Message + System.Environment.NewLine));
           }
           return ExecutionOutcome.CreateSuccessfulOutcome();
       }

Thats relatively "cutting edge" the C# crew, but its language concept is about as old as the hills. Here is the ballpark equivalent in LISP, a language concieved in the late 50's.

(apply
 (GetMessage '#),
 (mapcar
  (lambda (x)
   (if (IsValid x)
    nil,
    (CreateExecutionFailureOutcome("..." (ItemGroupName x))),
   )
  ),
  (ItemGroups Context)
 )
)

Lisp was a little on the cryptic side, but its true power was its declarative syntax. Lisp is a "functional language".

C# is a sequential language, with declarative extensions. Linq gives me the ability to jump in and out of "functional language" mode in C#. I find myself gradually turning back into a LISP programmer :)

One thing I wish I could do is take this kind of declarative power and apply it to SQL query plans, now that would impress me.

Sharepoint C# HTML Trick: Is this fluent programming or sleazy hack?

The challenge: writing custom sharepoint web-parts can be painful because there is no inline code markup. (and I'm NOT using the "smart part" )

How to write HTML using nothing but C#?
HTML is a tree just like any other AST.

This is the code I wanted to write:

<asp:Table Width="100%">
        <asp:TableRow>
            <asp:TableCell Width="100%" CssClass="headerRow">Alphabetical Search</asp:TableCell>
        </asp:TableRow>
        <asp:TableRow>
            <asp:TableCell Width="100%">
                <asp:GridView runat="server" Width="100%" />
            </asp:TableCell>
        </asp:TableRow>
    </asp:Table>

This is the code equivalent (plus databinding) using fluent constructors using C#:

protected override void CreateChildControls()

        {

            var dataFeed = new List

                               {

                                   "one",

                                   "two",

                                   "three"

                               };

            var gridView = new GridView

                               {

                                   Width = new Unit("100%"),

                                   DataSource = dataFeed,

                                   Visible = true

                               };

            gridView.DataBind();

            var table = new Table

                            {

                                Width = new Unit("100%"),

                                Rows =

                                    {

                                        new TableRow

                                            {

                                                Cells =

                                                    {

                                                        new TableCell

                                                            {

                                                                Text = "Alphabetical Search",

                                                                CssClass = "headerRow"

                                                            }

                                                    }

                                            },

                                        new TableRow

                                            {

                                                Cells =

                                                    {

                                                        new TableCell

                                                            {

                                                                Controls =

                                                                    {

                                                                        gridView 

                                                                    }

                                                            }

                                                    }

                                            }

                                    }

                            };

            Controls.Add(table);

            base.CreateChildControls();

        }

Nothing earth shattering here, but I actually dont mind using this syntax. This is the result:







Do you like it?