How to replace text in a ruby string

Question

I am trying to write a very simple method in Ruby which takes a string and an array of words and checks if the string contains any of the words and if it does it replaces them with their uppercase.

I made an attempt but its not great due to my level of Ruby skills.

def(my_words,my_sentence)
  #split the sentence up into an array of words
  my_sentence_words =  my_sentence.split(/\W+/)
  #nested loop that checks the words array for each brand 
  my_sentence_words.each do |i|
    my_words.each do |i|
      #if it finds a brand in the words and sets them to be uppercase
      if my_words[i] == my_sentence_words[i]
        my_sentence_words[i] == my_sentence_words[i].up.case
      end
    end
  end

  #put the words array into one string
  words.each do |i|
    new_sentence = ("" + my_sentence_words[i]) + " "
  end
end

I am getting: can't convert string into integer error

For one thing you are using i twice, use j for the inner loop. Second, you didn't give your function a name. List the full error. — Dan Grahn
– Dan Grahn, Commented Dec 10, 2013 at 18:15
"Questions concerning problems with code you've written must describe the specific problem — and include valid code to reproduce it — in the question itself. See SSCCE.org for guidance." — the Tin Man
– the Tin Man, Commented Dec 10, 2013 at 18:22
As you gain experience with Ruby you'll find that you don't loop on indices nearly as often as you may be accustomed with C and the like. You'll be relying more on each and the numerous methods in the Enumerable "mixin" (module), nearly all of which are implemented with each. — Cary Swoveland
– Cary Swoveland, Commented Dec 10, 2013 at 19:25

Dan Grahn · Accepted Answer · 2013-12-10 19:04:21Z

3

def convert(mywords,sentence)
 regex = /#{mywords.join("|")}/i
 sentence.gsub(regex) { |m| m.upcase }
end
convert(%W{ john james jane }, "I like jane but prefer john")
#=> "I like JANE but prefer JOHN"

edited Dec 10, 2013 at 19:04

Dan Grahn

9,4446 gold badges41 silver badges77 bronze badges

answered Dec 10, 2013 at 18:22

bjhaid

9,8502 gold badges41 silver badges47 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Cary Swoveland Over a year ago

Note convert(%W{ JANE }, "I like JANE") => "I like " and convert(%W{ JANE }, "I like jane") => "I like jane". You need to add /i and remove !.

the Tin Man Over a year ago

Be careful with /#{mywords.join("|")}/i. It will create a pattern that allows sub-string matches, not whole-word matches. /\b#{mywords.join("|")}\b/i would be better.

the Tin Man · Accepted Answer · 2016-10-20 01:28:18Z

3

This will work better. It loops through the brands, searches for each, and replaces with the uppercase version.

brands = %w(sony toshiba)
sentence = "This is a sony. This is a toshiba."

brands.each do |brand|
  sentence.gsub!(/#{brand}/i, brand.upcase)
end

Results in the string.

"This is a SONY. This is a TOSHIBA."

For those who like Ruby foo!

sentence.gsub!(/#{brands.join('|')}/i) { |b| b.upcase }

And in a function

def capitalize_brands(brands, sentence)
  sentence.gsub(/#{brands.join('|')}/i) { |b| b.upcase }
end

edited Oct 20, 2016 at 1:28

the Tin Man

161k44 gold badges222 silver badges308 bronze badges

answered Dec 10, 2013 at 18:19

Dan Grahn

9,4446 gold badges41 silver badges77 bronze badges

5 Comments

user2527785 Over a year ago

Thanks, also one other question for example if I am using this code in my rails app and wanted to take a string and replace a wordd with a link to a url so it would go to brands/sony etc. How could I put a link inside of a string?

Dan Grahn Over a year ago

Just use link_to b.upcase, 'YOUR_URL'

Cary Swoveland Over a year ago

mutt, does link_to require a require?

Dan Grahn Over a year ago

It shouldn't if you are using it in a helper.

Cary Swoveland Over a year ago

It appears to be from ActionView::Helpers, which I presume is used with Rails. That's what I meant about a require, as the question is not tagged with Rails.

yozzz · Accepted Answer · 2014-01-16 20:49:12Z

0

You get this error because i doesn't start from 0 as you expected, in each method i is an element of array, and has string type, it's a first word from your sentence:

my_sentence_words = ["word"]
my_sentence_words.each do |i|
  puts i.length #=> 4
  puts i.type   #=> String
  puts i        #=> word
end

So you try to call my_sentence_words[word] instead of my_sentence_words[0]. You can try method each_index that passes index of element instead of element itself`:

def check(str, *arr)
  upstr = str.split(' ')
  upstr.eachindex do |i|       #=> i is index
    arr.each_index do  |j|  
      upstr[i].upcase! if upstr[i] == arr[j]        
    end
  end
  upstr
end

check("This is my sentence", "day", "is", "goal", "may", "my")
#=>["This", "IS", "MY", "sentence"]

edited Jan 16, 2014 at 20:49

answered Dec 11, 2013 at 16:39

yozzz

1,2871 gold badge22 silver badges31 bronze badges

Collectives™ on Stack Overflow

How to replace text in a ruby string

3 Answers 3

2 Comments

5 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

5 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related