Expression trees is an obscure, although very interesting feature in .NET. Most people probably think of it as something synonymous with object-relational mapping frameworks, but despite being its most common use case, it’s not the only one. There are a lot of creative things you can do with expression trees, including code generation, transpilation, metaprogramming, and more. During this talk, I will explain what this feature really is about and guide you through some examples where it provides real-life benefits.

We'll talk about:

• What is an expression tree
• How to compile code at runtime
• How to make reflection faster
• How to implement generic operators
• How to turn DSLs into expression trees
• How to make metaprogramming type-safe
• How to translate a lambda into a different language...and more