Skip to main content

My First Ruby Program (pt. 1 in a series)

I've decided to chart my progress on picking up Ruby as a programming language.

The first program I was going to go for is a program that reverses text.When I worked with graphics, I found that many times Arabic and Hebrew texts ended up being reversed. Because while they are written from right-to-left, these languages are displayed in special ways by Word Processing programs. They allow you to enter the text as it'd would be written, but save left-to-right, so that when you copy the text to a program that can't display the text in reverse order, they end up backwards.

This is such a common problem that most modern graphic programs (like GIMP) now allow you to enter text in both left-to-right as well as right-to-left order. But not all and not old ones. So what I want is to make a program that will take a text file and reverse the order of each line without reversing the order of the lines. Structurally this is quite simple you take each character put it in a stack and then write them out in the last-one-in, first-one-out order like you were putting each character in a bag and then taking it out. But I wanted to do this in object-oriented mode.

So here's what I've got so far:

First thing I learned that made me super happy is that there is a method in Ruby called reverse, that lets you reverse the text without having to do the stack step by step nightmare (like you would have to in say pure C or a lower level language like Assembly).

The first line require 'rubygems' calls another library but I'm not using it, I just saw it and though I better put it in, in case I need it. Then we get to the line that was missing the first time I wrote this program: text = Here we create the variable, we make it an object (so it can have a reverse method in it!) and this is the step I was missing till today.

The rest is a little fun piece of code I learned yesterday.

Dir["ToReverse-*.txt"].each do |filename|

This calls the Dir class method to look for all files in that folder (in the same Directory, get it?) that are prefaced with "ToReverse-" and end it ".txt" and will spit-out the filename of each one. Then to each one it will get the file name assigned to a transitory variable called filename.
text = filename )
Here I have the text object be filled up with the contents of each file. Which works fine for one file, but not sure what happens with more than one. Time to experiment. 

The rest of it merely calls the reverse method with imperative (the exclamation mark means the text variable will get re-written by the output). Out puts text then ends the loop.

What I want to do next is cut up the string at the line breaks and spit it into an array so that each element in the array is a line. Reverse each line then either print the array or write it to a file. But first I gotta figure out why the output screws up Hebrew.


Popular posts from this blog

How to configure Ubuntu's keyboard to work like a Mac's

Typing accents on a PC is a complicated Alt + three numbered code affair. One feels like a sorcerer casting a spell. "I summon thee accented é! I press the weird magical key Alt, and with 0191 get the flipped question mark!" For a bilingual person this meant that writing on the computer was a start-and-stop process. With Mac's it a whole lot easier, just Alt + e and the letter you wanted for accents and alt + ? for the question mark. No need to leave the keyboard for the number pad and no need to remember arcane number combinations or have a paper cheat sheet next to the keyboard, as I've seen in virtually every secretaries computer in Puerto Rico.

Linux has a interesting approach to foreign language characters: using a compose key. You hit this key which I typically map to Caps Lock and ' and the letter you want and voilá you get the accent. Kinda makes sense: single quotation mark is an accent, double gets you the ümalaut, works pretty well. Except for the ñ, wh…

Contrasting Styles of Writing: English vs. Spanish

There is interestingly enough a big difference between what's considered good writing in Spanish and English. V.S. Naipul winner of the 2001 Nobel prize for literature publish an article on writing. In it he emphasizes the use of short clear sentences and encourages the lack of adjectives and adverbs. Essentially he pushes the writer to abandon florid language and master spartan communication. This is a desired feature of English prose, where short clipped sentences are the norm and seamlessly flow into a paragraph. In English prose the paragraph is the unit the writer cares about the most.

This is not the case in Spanish where whole short stories (I'm thinking this was Gabriel Garcia Marquez but maybe it was Cortázar) are written in one sentence. Something so difficult to do in English that the expert translator could best manage to encapsulate the tale in two sentences. The florid language is what is considered good writing in Spanish but unfortunately this has lead to what …

Fixing Autocomplete in Github's Atom Text Editor for Ruby

I really like Github's Atom Text Editor. I really like that it's multi-platform allowing me to master one set of skills that is transferable to all platforms and all machines. 

On thing that just burns me of the default set-up in Atom is the Autocomplete feature that seems to change my words as a type them. Because Ruby uses the end of line as a terminus for a statement you usually finish a word with pressing the return button and you get really annoying changes to your finished typed word a la MS Word. I find myself yelling "No that's not what I wrote!" at the screen in busy coffee shops.

I disabled autocomplete for a while but it is a very useful function. Then I found out they changed the package that gave the autocomplete to a new one called "Autocomplete Plus" that gives you more options. All that I needed to change to make autocomplete sane again:

1. Open Atom's Preferences
2. Search the bundled packages for "Autocomplete Plus"

3. Go to t…