artemohanjanyan/university

Single repository for university projects

University projects

Computer Technology Department, ITMO University, 2014-present.

2 term

• C++. Big initeger arithmetics library and custom std::list<std::string> implementation from exam.
• Programming paradigms. Implementation of arithmetic expression parsing and evaluation in Java, JavaScript, and Clojure using different programming paradigms.

3 term

• Mathematical logic. Formal proof validators, deduction theorem, a proof generator for tautologies, and generator of a+b proof in formal arithmetics implemented in Haskell.
• C++. Custom implementation of optional and proxy server, written in modern C++. Latter includes low-level RAII wrappers for Linux networking interface for C, asynchronous I/O API backed by epoll, basic incremental HTTP request parser, multithreaded DNS-resolver for lower latency, and colorful log.
• Android course project. Android application for playing chess via Bluetooth. Team project.

4 term

• Type Theory course. Lambda calculus homework includes normalization algorithm and type inference algorithms for simply typed lambda calculus and Hindley-Milner type system, all implemented in Haskell. Idris code includes various formal proofs based on dependent types and Curry-Howard correspondence. Course notes in LaTeX (in Russian) which are worth many sleepless nights spent on them.
• Repository for Operating Systems course starring rshd server in (almost) pure C.
• Java technologies. Deeper Java course with homework covering different parts of Java API, including concurrency (HW 8 "web crawler") and reflection API (HW 3 "implementor", an application which generates dummy implementations of provided classes and interfaces).

5 term

• Computational geometry. Working with Delaunay triangulation in C++.

6 term

• Translation methods. Parser generator for LL(1) grammars and formula translator from TeX to MathML, implemented in Haskell.

university's Issues

Add support for Content-Length

Proxy

• Add registration to epoll_registration constructor (or maybe not?).
• Add on_connected helper function.
• eventfd
• resolver
• timer

tt:hw2

Fix crash on \x . x x

C++ TODO

• Add epoll pointer to epoll_registration and default on_close.

Normalization doesn't work

$ normalize
(\a.\x.a) x
\x'.x
$ normalize
(\a.\x.\x.a) x
normalize: src/Simple/Reduction.hs:82:5-70: Irrefutable pattern failed for pattern Right newExpr

At first sight the problem is in rename' function:

rename' act dict (Lambda var expr)
        | Map.member var dict = Lambda newVar $ rename' (Map.insert var newVar act) (Map.delete var dict) expr
        | Map.member var act  = Lambda var    $ rename' (Map.delete var act)        dict                  expr
        | otherwise           = Lambda var    $ rename' act                         dict                  expr

Seems, you should not delete bound variable from dict, or should replace it with actual value on second stage of the pattern matching above.