F# “enquoten” script
As part of my F# studies, I created a script that processes text files by (1) truncating lines to a specified maximum length and (2) prepending text (such as > ) to the beginning of lines, thereby quoting them as in plain text emails.
I’m still tinkering with it, but it has been a suprisingly good little exercise. I’m sure it can be done much better (and probably even as a crazy bash one-liner, though I’d argue this is far easier to debug 😄), but I’m pretty pleased with it as a relatively newbie to the language.
I had the idea to create a tool like this when I realized that it was a perfect chance for practicing tail-recursive functions.
Edit: I’ve since made several updates from the initial version and have added features such as computation expressions and generics as well!
Example
Source text from Wikipedia’s F# page, which I saved to a local text file:
F# (pronounced F sharp) is a general-purpose, strongly typed, multi-paradigm programming language that encompasses functional, imperative, and object-oriented programming methods. It is most often used as a cross-platform Common Language Infrastructure (CLI) language on .NET, but can also generate JavaScript and graphics processing unit (GPU) code.
F# is developed by the F# Software Foundation, Microsoft and open contributors. An open source, cross-platform compiler for F# is available from the F# Software Foundation. F# is a fully supported language in Visual Studio and JetBrains Rider. Plug-ins supporting F# exist for many widely used editors including Visual Studio Code, Vim, and Emacs.
F# is a member of the ML language family and originated as a .NET Framework implementation of a core of the programming language OCaml. It has also been influenced by C#, Python, Haskell, Scala and Erlang.
Output from dotnet fsi Enquoten.fsx 40 "> " ~/Downloads/fsharp.txt:
> F# (pronounced F sharp) is a
> general-purpose, strongly typed,
> multi-paradigm programming language
> that encompasses functional,
> imperative, and object-oriented
> programming methods. It is most often
> used as a cross-platform Common
> Language Infrastructure (CLI)
> language on .NET, but can also
> generate JavaScript and graphics
> processing unit (GPU) code.
>
> F# is developed by the F# Software
> Foundation, Microsoft and open
> contributors. An open source,
> cross-platform compiler for F# is
> available from the F# Software
> Foundation. F# is a fully supported
> language in Visual Studio and
> JetBrains Rider. Plug-ins supporting
> F# exist for many widely used editors
> including Visual Studio Code, Vim,
> and Emacs.
>
> F# is a member of the ML language
> family and originated as a .NET
> Framework implementation of a core of
> the programming language OCaml. It
> has also been influenced by C#,
> Python, Haskell, Scala and Erlang.