Difference between revisions of "FP Laboratory 1"

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It should report a problem in function <code>plus</code> (you can not use <code>+</code> with letter, it can be repaired by removing <code>+ 'a'</code>). Report from VS Code is refreshed whenever the source file is saved on disk.
 
It should report a problem in function <code>plus</code> (you can not use <code>+</code> with letter, it can be repaired by removing <code>+ 'a'</code>). Report from VS Code is refreshed whenever the source file is saved on disk.
 
</translate>
 
</translate>
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== First program in Haskell ==
 +
In your favorite development environment (VS Code by default):
 +
* Crate a file <code>simple.hs</code>.
 +
* Create a function <code>pythagoras a b</code> that computes <code>c</code> based on  <math>c^2 = a^2 + b^2 \,,</math>.

Revision as of 12:27, 28 August 2019

Working environment

Using the installation guide from Functional programming prepare your working environment.

How to verify it is working?

  • Run ghci from the command line. it will start GHC Interpreter, the output should be something like this:
GHCi, version 8.6.5: http://www.haskell.org/ghc/  :? for help
Prelude>
  • If you write expression, for example 1+2*3, it should be evaluated. You can close this interpreter by typing :q.
  • Open Visual Studio Code, create a file simple.hs and put there following lines of code:
doubleMe x = x * x

plus x y  = x + y + 'a'

It should report a problem in function plus (you can not use + with letter, it can be repaired by removing + 'a'). Report from VS Code is refreshed whenever the source file is saved on disk.

First program in Haskell

In your favorite development environment (VS Code by default):

  • Crate a file simple.hs.
  • Create a function pythagoras a b that computes c based on .