mikeobrien

private static IEnumerable<UnionVisitor<TQuerySource>.UnionExpression> GetUnionExpressions(Expression expression)
{
    Func<Expression, IEnumerable<UnionVisitor<TQuerySource>.UnionExpression>> getVisitorExpressions = x =>
                                {
                                    var unionVisitor = new UnionVisitor<TQuerySource>();
                                    unionVisitor.Visit(x);
                                    return unionVisitor.Expressions;
                                };
    return GetUnionExpressions(getVisitorExpressions(expression), getVisitorExpressions);
}

mikeobrien

let GetUnionExpressions<'a> expression =
     
    let getVisitorExpressions expression =
        let unionVisitor = new UnionVisitor<'a>()
        unionVisitor.Visit(expression : Expression) |> ignore
        unionVisitor.Expressions

    let rec getUnionExpressions (expressions : seq<UnionVisitor<'a>.UnionExpression>) = 
        if expressions |> Seq.isEmpty then Seq.empty
        else expressions 

mikeobrien

public abstract class ExpressionVisitorBase<TState>
{
    public class ExpressionNotSupportedException : Exception
    {
        public ExpressionNotSupportedException(Expression expression) :
            base(string.Format("Expression {0} not supported.", expression.GetType().Name)) { }
    }

    public virtual TState Visit(Expression node)
    {

mikeobrien

"Sometimes the only way you can feel good about yourself is by making someone else look bad. And I'm tired of making other people feel good about themselves." ~Homer J Simpson

mikeobrien

require "fileutils"

module FileSystem

    def FileSystem.EnsurePath(path)
        if !Dir.exists?(path) then 
            FileUtils.mkdir_p(path)
        end
    end

mikeobrien

public static class MaybeMonadicExtensions
{
    public static Maybe<T> ToMaybe<T>(this T value)
    {
        return value == null ? Maybe.Nothing<T>() : Maybe.Just(value);
    }

    public static Maybe<B> Bind<A, B>(this Maybe<A> a, Func<A, Maybe<B>> func)
    {
        return a.HasValue ? func(a.Value) : Maybe.Nothing<B>();

mikeobrien

// http://stevesmithblog.com/blog/how-do-i-use-structuremap-with-asp-net-mvc-3/

return _container.GetAllInstances<object>().Where(s => s.GetType() == serviceType);

// Isn't this a better way to do it?

return _container.GetAllInstances(serviceType).Cast<object>();

mikeobrien

// Some function
Func<int, int, int, int> multiplyThree = (a, b, c) => a * b * c;

// Lets curry it by breaking it up into multiple functions that only have one arg
Func<int, Func<int, Func<int, int>>> multiplyThreeCurried = (a) => (b) => (c) => multiplyThree(a, b, c);

// This is curried, yay!
var result = multiplyThreeCurried(10)(2)(3);

// This is partially applied

mikeobrien

public static IEnumerable<object> GetAllInstances(this IContainer container, IEnumerable<Type> types)
{
    return container.Model.AllInstances.
        Join(types, x => x.PluginType, y => y, (x, y) => x).
        Select(x => x.ConcreteType).
        Distinct().
        Select(container.GetInstance);
}

mikeobrien

// This one liner:

return GetState().Map(x => x.ContainsKey(key) ? x[key] : null);

// Instead of this multiliner

var state = GetState();
return state.ContainsKey(key) ? state[key] : null;