Question

Is their an equivalent to C#’s Expression API in scala?

For example, I would like to have a lambda like this:

(Foo) => Foo.bar

and be able to access “bar” in the function it is passed to.

Answer 1

This is not supported by Scala. ScalaQL: Language-Integrated Database Queries
for Scala describes a LINQ-like functionality in Scala:

While it is possible for Microsoft to
simply extend their language with this
particular feature, lowly application
developers are not so fortunate. For
exam- ple, there is no way for anyone
(outside of Sun Microsystems) to
implement any form of LINQ within Java
because of the language modications
which would be required. We faced a
similar problem attempting to
implement LINQ in Scala.

Fortunately, Scala is actually
powerful enough in and of itself to
implement a form of LINQ even without
adding support for expression trees.
Through a combination of operator
overloading, implicit conversions, and
controlled call- by-name semantics, we
have been able to achieve the same
eect without making any changes to
the language itself.