An expression is said to be referentially transparent if it can be replaced with its value without changing the behavior of a program (in other words, yielding a program that has the same effects and output on the same input)
https://en.wikipedia.org/wiki/Referential_transparency
This example is taken from the book "Functional Programming in Scala"
The following is referentially transparent:
scala> val x = "hello, world"
| private def updateReturning[A, F]( | |
| returningQuery: Query[A, F, C], v: U): SqlStreamingAction[Vector[F], F, Effect.All] = { | |
| val ResultSetMapping( | |
| _, CompiledStatement(_, sres: SQLBuilder.Result, _), CompiledMapping(_updateConverter, _)) = | |
| updateCompiler.run(updateQuery.toNode).tree | |
| val pconv: SetParameter[U] = { | |
| val ResultSetMapping(_, compiled, CompiledMapping(_converter, _)) = | |
| updateCompiler.run(updateQuery.toNode).tree | |
| val converter = _converter.asInstanceOf[ResultConverter[JdbcResultConverterDomain, U]] |
In this article I’ll tell you about my pure functional library for Software Transactional Memory (STM) that I’ve built in C++. I adopted some advanced functional programming concepts that make it composable and convenient to use. Its implementation is rather small and robust, which differentiates the library from competitors. Let’s discuss what STM is and how to use it.
sudo dnf remove gnome-tour gnome-abrt gnome-calculator gnome-calendar gnome-maps gnome-weather \
rhythmbox gnome-contacts totem gnome-logs gnome-photos gnome-clocks gedit gnome-system-moniter \
gnome-user-docs gnome-screenshot gnome-remote-desktopsudo dnf remove fedora-chromium-config