derekmorr

Last week we refactored some Python code that parses CSV files and loads records into a database. We ended up with two general groups of code.

One group (lines 24 - 43) is a series of small functions that extract various data types (booleans, timestamps, etc) from CSV fields. The other group is a large function (lines 46 - 92) that extracts individual fields and builds a model object. I expressed frustration that this latter function was so long.

def build_nessus_object(row, heading_map):
    """process a row of data and return a Nessus object"""
    # parameters which are processed as-is from the csv
    normal_params = {
        'plugin' : 'Plugin',

derekmorr

module Ch17 where

import           Control.Applicative
import Data.List (elemIndex)
import Data.Monoid

-- 1
added :: Maybe Integer
added = (+3) <$> (lookup 3 $ zip [1, 2, 3] [4, 5, 6])

derekmorr

use std::cmp;

fn sum(numbers: Vec<i32>) -> i32 {
    numbers.iter().fold(0, |total, num| total + num)
}

fn biggest_word(words: Vec<&str>) -> usize {
    words.iter().fold(0, |length, word| cmp::max(length, word.chars().count()))
}

derekmorr

import org.scalacheck.Gen.choose
import org.scalatest.prop.GeneratorDrivenPropertyChecks
import org.scalatest.{WordSpec, MustMatchers}

class TruncateTest extends WordSpec with MustMatchers with GeneratorDrivenPropertyChecks {

  def truncate(str: String, length: Int): String = {
    if (str.length < length)
      str
    else if (length < 3 || str.length < 3)

derekmorr

module Chapter11Tree where

data OperatingSystem = Linux
                     | OpenBSD
                     | Mac
                     | Windows
                     deriving (Eq, Show)
                     
data ProgrammingLanguage = Haskell
                         | Agda

derekmorr

module Chapter11Phone where

import Data.Char (isLetter, isNumber, isUpper, toLower)
import Data.List (group, sort)

data CharType = Letter Char
              | Number Char
              | Punctuation Char
              deriving (Eq, Show)

derekmorr

module DSLFSM where
    
import Data.Char (toLower, toUpper)

-- a DSL for basic text processing
-- and a FSM for implementing that DSL.
-- adapted to Haskell from https://www.youtube.com/watch?v=7D9GE3-o54o

data MachineState = Normal | Comment | Upper | Lower

derekmorr

open System

type GunRecord =
 { xcoord : float
   ycoord : float
   speed : float
   distance : float
   name : String }
  
type GunResult =

derekmorr

open System

let GoldenTuples numbers =
  let GoldenRatio = (1.0 + Math.Sqrt(5.0)) / 2.0
  seq {
    for n in numbers do
      yield (n, (float n) * GoldenRatio)
  }

let rec GetNumber numbers =

derekmorr

open System

let readConsoleValue prompt =
  printf "%s: " prompt
  Console.ReadLine()

let classifyAge name age =
  if age >= 20 then
    sprintf "%s is no longer a teenager" name
  elif (age < 20 && age > 13) then