C# Paradigms: Side effects on Lists

Question

I am trying to evolve my understanding of side effects and how they should be controlled and applied.

In the following List of flights, I want to set a property of e

Answer 1

You should break that up into two blocks of code, one for the retrieval and one for setting the value:

var nonStopFlights = fResults.Where(f => f.NonStop);

foreach(var flight in nonStopFlights)
    flight.Description = "Fly Direct!";

Or, if you really hate the look of foreach you could try:

var nonStopFlights = fResults.Where(f => f.NonStop).ToList();

// ForEach is a method on List that is acceptable to make modifications inside.
nonStopFlights.ForEach(f => f.Description = "Fly Direct!");