I don't think people understanding the problem LINQ attempts to solve with expression trees. Let me give you a more Internet'ish example. Let's say I have a R

I don't think people understanding the problem LINQ attempts to solve with expression trees. Let me give you a more Internet'ish example. Let's say I have a REST api that's something like this: https://movies.org/movie https://movies.org/movie which returns all movies but if you want only certain movies, you issue: https://movies.org/movie?year>2016 https://movies.org/movie?year>2016 to get movies created after 2016. Let's say you didn't issue the query but instead you got the entire set of movies and filtered locally: var movies = get("https://movies.org/movie" https://movies.org/movie") foreach( var movie in movies) { if (movie.year > 2016) addToTable(movie) } Let's do this with LINQ: foreach( var movie in movies.Where(movie => movie > 2016)) { addToTable(movie) } The naive observer will assume the two pieced of code are about the same. But in actuality, if you had a fictitious "LINQ to Movies", it could, internally, construct the correct REST API for you. What I'm saying is that, this code: var list = movies.Where(movie => movie > 2016)) would translate into: var movies = get("https://movies.org/movie?year>2016" https://movies.org/movie?year>2016") Not so hypothetical. This is how OData works from C#. Look at the C# example under "Step 2: Requesting an individual resource" at http://www.odata.org/getting-started/understand-odata-in-6-steps/ http://www.odata.org/getting-started/understand-odata-in-6-s... See how elegant it is compared to the other examples using Java, Node, etc. Doing this requires meta-programming, which many other languages have. I don't know much about Clojure, Scala or Ruby, but I'm pretty sure stuff like this can be (and possibly already are) built using the existing meta-programming constructs.