16 posts tagged with "c#"

polynomials-pratt-algorithm​

Using a Pratt parser I aim to parse expressions like this x^2+y^2-1, x=1, y=1 and xy, x=2, y=3. Parsing mathematical expressions it's not hard but it already contains some interesting behaviour such as associativity between operators x+y*z is equal to x+(y*z) and not (x+y)*z. For no particular reason I decided to put the variable assignments after the polynomial. The expression x^2+y^2-1, x=1, y=1 is to be interpreted as you would with this pseudo code

Antlr4​

A few years back I was playing with Antlr to build a polynomial evaluator. The result was working but not very sofisticated o particularly good, just a minimal working example. In these days of quarantine in Italy, I decided to get back a that project and try to make something better. The final result can be found at this repo.

2021-09-29 I added an example on how to use ROP in an ASP.NET Core project here

A few days back I was reading about Railway oriented programming (ROP) on the awesome fsharpforfunandprofit website. Scott Wlaschin (SW) describe a functional approach to error handling not regarding only exceptions but in general how to handle deviations from the happy path. I really liked his approach and I tried to translate the F# code to C# and in this post I'll briefly recap what I've learned.

Antlr4​

Update April 2020, hey! I updated this article and the corresponding repo check it out here

In the last couple of months I've been reading and studying about compilers and languages and for everyone doing something like that it's very easy to meet Antlr at a certain point. What is antlr?

The problem​

The bottom navigation is a very simple and easy template from Android Studio, the porting took 15 minutes at most and the result is quite appealing.

The problem​

Last week I was trying for the first time to write a simple app using Xamarin. I wanted a "material design" menu which after some research I understood to be a navigation drawer.