Trying to iterate over some phrases, and whenever I find a word, I need to replace it with a link.
phrases = ["hello world", "worldwide"]
words_to_link = ["world", "world"]
I am trying to get:
"hello <a href='world'>world</a><br />worldwide"
My code is:
phrases.each do |ph|
words_to_link.each do |w|
ph.gsub!(w, "<a href='#{w}'>#{w}</a>")
end
end.join("<br />").html_safe
The output of this is:
"hello <a href='<a href='world'>world</a>'><a href='world'>world</a></a><br /><a href='<a href='world'>world</a>'><a href='world'>world</a></a>wide"
On the first run it finds all occurrences of world, but on the second, it goes inside the generated world and gsubs again.
Another problem is the proper regex to only find words by boundaries, I thought it would be /\b(word)\b, but that didn't work.
Any pointers?
I'm a little confused by your question, so may have got the wrong end of the stick here. However, here is an answer by my interpretation:
phrases = ["hello world", "worldwide"]
substitutions = { /\bworld\b/ => "world" }
phrases.each do |ph|
substitutions.each do |pattern, replacement|
ph.gsub!(pattern, "<a href='#{replacement}'>#{replacement}</a>")
end
end
phrases.join("<br />").html_safe
You can use \b in a regex to mark a work boundary, to avoid altering the "worldwide" string. And (I think this is what you wanted?) you can define some mapping between the search/replace terms rather than looping though twice, to avoid the double-replacement.
Related
I got a few string like so:
TFjyg9780878_867978-DGB097908-78679iuhi698_widesky_light_87689uiyhk
AND
TFjyg9780878_867978-DGB097908-78679iuhi698_sky_light_87689uiyhk
AND
TFjyg9780878_867978-DGB097908-78679iuhi698_widesky_dark_87689uiyhk
AND
TFjyg9780878_867978-DGB097908-78679iuhi698_sky_dark_87689uiyhk
I need to check whether the strings above has one of the widesky_light, sky_light, widesky_dark and sky_dark with exactitude so I wrote this:
if my_string.match("widesky_light")
...
end
For each variant, but the problem I'm having is because sky_light and widesky_light are similar, my code is not working properly. I believe the solution to the above would be a regex, but I've spend the afternoon yesterday trying to get it to work without much success.
Any suggestions?
EDIT
A caveat: in this string (as example): TFjyg9780878_867978-DGB097908-78679iuhi698_widesky_light_87689uiyhk, the part after widesky_light, which is _87689uiyhk is optional, meaning that sometimes I have it, sometimes I don't, so a solution would not be able to count on _string_.
Looks like you just need to reorder your if statements
if my_string.match(/widesky_light/)
return 'something'
end
if my_string.match(/sky_light/)
return 'something'
end
Regex
1st regex : extract word for further checking
Here's a regex which only matches the interesting part :
(?<=_)[a-z_]+(?=(?:_|\b))
It means lowercase word with possible underscore inside, between 2 underscores or after 1 underscore and before a word boundary.
If you need some logic depending on the case (widesky, sky, light or dark), you could use this solution.
Here in action.
2nd regex : direct check if one of 4 words is present
If you just want to know if any of the 4 cases is present :
(?<=_)(?:wide)?sky_(?:dark|light)(?=(?:_|\b))
Here in action, with either _something_after or nothing.
Case statement
list = %w(
TFjyg9780878_867978-DGB097908-78679iuhi698_widesky_light_87689uiyhk
TFjyg9780878_867978-DGB097908-78679iuhi698_sky_light_87689uiyhk
TFjyg9780878_867978-DGB097908-78679iuhi698_widesky_dark_87689uiyhk
TFjyg9780878_867978-DGB097908-78679iuhi698_sky_dark_87689uiyhk
TFjyg9780878_867978-DGB097908-78679iuhi698_trash_dark_87689uiyhk
)
list.each do |string|
case string
when /widesky_light/ then puts "widesky light found!"
when /sky_light/ then puts "sky light found!"
when /widesky_dark/ then puts "widesky dark found!"
when /sky_dark/ then puts "sky dark found!"
else puts "Nothing found!"
end
end
In this order, the case statement should be fine. widesky_dark won't match twice, for example.
Maybe something like this:
case my_string
when /_(sky_light)/
# just sky_light
when /sky_light/
# widesky_light
when /_(sky_dark)/
# just sky_dark
when /sky_dark/
# widesky_dark
else
puts "I don't like"
end
A while ago I created a function in PHP to "twitterize" the text of tweets pulled via Twitter's API.
Here's what it looked like:
function twitterize($tweet){
$patterns = array ( "/((([A-Za-z]{3,9}:(?:\/\/)?)(?:[-;:&=\+\$,\w]+#)?[A-Za-z0-9.-]+|(?:www.|[-;:&=\+\$,\w]+#)[A-Za-z0-9.-]+)((?:\/[\+~%\/.\w-_]*)?\??(?:[-\+=&;%#.\w_]*)#?(?:[\w]*))?)/",
"/(?<=^|(?<=[^a-zA-Z0-9-\.]))#([A-Za-z_]+[A-Za-z0-9_]+)/",
"/(?<=^|(?<=[^a-zA-Z0-9-\.]))#([A-Za-z_]+[A-Za-z0-9_]+)/");
$replacements = array ("<a href='\\0' target='_blank'>\\0</a>", "<a href='http://twitter.com/\\1' target='_blank'>\\0</a>", "<a href='http://twitter.com/search?q=\\1&src=hash' target='_blank'>\\0</a>");
return preg_replace($patterns, $replacements, $tweet);
}
Now I'm a little stuck with Ruby's gsub, I tried:
def twitterize(text)
patterns = ["/((([A-Za-z]{3,9}:(?:\/\/)?)(?:[-;:&=\+\$,\w]+#)?[A-Za-z0-9.-]+|(?:www.|[-;:&=\+\$,\w]+#)[A-Za-z0-9.-]+)((?:\/[\+~%\/.\w-_]*)?\??(?:[-\+=&;%#.\w_]*)#?(?:[\w]*))?)/", "/(?<=^|(?<=[^a-zA-Z0-9-\.]))#([A-Za-z_]+[A-Za-z0-9_]+)/", "/(?<=^|(?<=[^a-zA-Z0-9-\.]))#([A-Za-z_]+[A-Za-z0-9_]+)/"]
replacements = ["<a href='\\0' target='_blank'>\\0</a>",
"<a href='http://twitter.com/\\1' target='_blank'>\\0</a>",
"<a href='http://twitter.com/search?q=\\1&src=hash' target='_blank'>\\0</a>"]
return text.gsub(patterns, replacements)
end
Which obviously didn't work and returned an error:
No implicit conversion of Array into String
And after looking at the Ruby documentation for gsub and exploring a few of the examples they were providing, I still couldn't find a solution to my problem: How can I have gsub handle multiple patterns and multiple replacements at once?
Well, as you can read from the docs, gsub does not handle multiple patterns and replacements at once. That's what causing your error, quite explicit otherwise (you can read that as "give me a String, not an Array!!1").
You can write that like this:
def twitterize(text)
patterns = [/((([A-Za-z]{3,9}:(?:\/\/)?)(?:[-;:&=\+\$,\w]+#)?[A-Za-z0-9.-]+|(?:www.|[-;:&=\+\$,\w]+#)[A-Za-z0-9.-]+)((?:\/[\+~%\/.\w-_]*)?\??(?:[-\+=&;%#.\w_]*)#?(?:[\w]*))?)/, /(?<=^|(?<=[^a-zA-Z0-9-\.]))#([A-Za-z_]+[A-Za-z0-9_]+)/, /(?<=^|(?<=[^a-zA-Z0-9-\.]))#([A-Za-z_]+[A-Za-z0-9_]+)/]
replacements = ["<a href='\\0' target='_blank'>\\0</a>",
"<a href='http://twitter.com/\\1' target='_blank'>\\0</a>",
"<a href='http://twitter.com/search?q=\\1&src=hash' target='_blank'>\\0</a>"]
patterns.each_with_index do |pattern, i|
text.gsub!(pattern, replacements[i])
end
text
end
This can be refactored into more elegant rubyish code, but I think it'll do the job.
The error was because you tried to use an array of replacements in the place of a string in the gsub function. Its syntax is:
text.gsub(matching_pattern,replacement_text)
You need to do something like this:
replaced_text = text.gsub(pattern1, replacement1)
replaced_text = replaced_text.gsub(pattern2, replacement2)
and so on, where the pattern 1 is one of your matching patterns and replacement is the replacement text you would like.
I'm trying to pass more than one regex parameter for parts of a string that needs to be replaced. Here's the string:
str = "stands in hall "Let's go get to first period everyone" Students continue moving to seats."
Here is the expected string:
str = "stands in hall "Let's go get to first period everyone" Students continue moving to seats."
This is what I tried:
str.gsub(/'|"/, "'" => "\'", """ => "\"")
This is what I got:
"stands in hall \"Let's go get to first period everyone\" Students continue moving to seats."
How do I get the quotes in while sending in two regex parameters using gsub?
This is an HTML unescaping problem.
require 'cgi'
CGI.unescape_html(str)
This gives you the correct answer.
From my comments on this question:
Your updated version is correct. The only reason the slashes are in your final line of code is that it's an escape sequence so that you don't mistakenly think the first slash is used to terminate the string. Try assigning your output and printing it:
str1 = str.gsub(/'|"/, "'" => "\'", """ => "\"")
puts str1
and you'll see that the slashes are gone when str1 is printed using puts.
The difference is that autoevaluating variables within irb (which is what I assume you're doing to execute this sample code) automatically calls the inspect method, which for string variables shows the string in its entirety.
Because I did not understand unescaping characters I found an alternative solution that might be the "rails-way"
Can you use <%= raw 'some_html' %>
My final solution ended up being this instead of messy regex and requiring CGI
<%= raw evidence_score.description %>
Unescaping HTML string in Rails
I have an automated report tool (corp intranet) where the admins have a few text area boxes to enter some text for different parts of the email body.
What I'd like to do is parse the contents of the text area and wrap any hyperlinks found with link tags (so when the report goes out there are links instead of text urls).
Is ther a simple way to do something like this without figuring out a way of parsing the text to add link tags around a found (['http:','https:','ftp:] TO the first SPACE after)?
Thank You!
Ruby 1.87, Rails 2.3.5
Make a helper :
def make_urls(text)
urls = %r{(?:https?|ftp|mailto)://\S+}i
html_text = text.gsub urls, '\0'
html_text
end
on the view just call this function , you will get the expected output.
like :
irb(main):001:0> string = 'here is a link: http://google.com'
=> "here is a link: http://google.com"
irb(main):002:0> urls = %r{(?:https?|ftp|mailto)://\S+}i
=> /(?:https?|ftp|mailto):\/\/\S+/i
irb(main):003:0> html = string.gsub urls, '\0'
=> "here is a link: http://google.com"
There are many ways to accomplish your goal. One way would be to use Regex. If you have never heard of regex, this wikipedia entry should bring you up to speed.
For example:
content_string = "Blah ablal blabla lbal blah blaha http://www.google.com/ adsf dasd dadf dfasdf dadf sdfasdf dadf dfaksjdf kjdfasdf http://www.apple.com/ blah blah blah."
content_string.split(/\s+/).find_all { |u| u =~ /^https?:/ }
Which will return: ["http://www.google.com/", "http://www.apple.com/"]
Now, for the second half of the problem, you will use the array returned above to subsititue the text links for hyperlinks.
links = ["http://www.google.com/", "http://www.apple.com/"]
links.each do |l|
content_string.gsub!(l, "<a href='#{l}'>#{l}</a>")
end
content_string will now be updated to contain HTML hyperlinks for all http/https URLs.
As I mentioned earlier, there are numerous ways to tackle this problem - to find the URLs you could also do something like:
require 'uri'
URI.extract(content_string, ['http', 'https'])
I hope this helps you.
I have a Rails site, where the content is written in markdown. I wish to display a snippet of each, with a "Read more.." link.
How do I go about this? Simple truncating the raw text will not work, for example..
>> "This is an [example](http://example.com)"[0..25]
=> "This is an [example](http:"
Ideally I want to allow the author to (optionally) insert a marker to specify what to use as the "snippet", if not it would take 250 words, and append "..." - for example..
This article is an example of something or other.
This segment will be used as the snippet on the index page.
^^^^^^^^^^^^^^^
This text will be visible once clicking the "Read more.." link
The marker could be thought of like an EOF marker (which can be ignored when displaying the full document)
I am using maruku for the Markdown processing (RedCloth is very biased towards Textile, BlueCloth is extremely buggy, and I wanted a native-Ruby parser which ruled out peg-markdown and RDiscount)
Alternatively (since the Markdown is translated to HTML anyway) truncating the HTML correctly would be an option - although it would be preferable to not markdown() the entire document, just to get the first few lines.
So, the options I can think of are (in order of preference)..
Add a "truncate" option to the maruku parser, which will only parse the first x words, or till the "excerpt" marker.
Write/find a parser-agnostic Markdown truncate'r
Write/find an intelligent HTML truncating function
Write/find an intelligent HTML truncating function
The following from http://mikeburnscoder.wordpress.com/2006/11/11/truncating-html-in-ruby/, with some modifications will correctly truncate HTML, and easily allow appending a string before the closing tags.
>> puts "<p><b>Something</p>".truncate_html(5, at_end = "...")
=> <p><b>Someth...</b></p>
The modified code:
require 'rexml/parsers/pullparser'
class String
def truncate_html(len = 30, at_end = nil)
p = REXML::Parsers::PullParser.new(self)
tags = []
new_len = len
results = ''
while p.has_next? && new_len > 0
p_e = p.pull
case p_e.event_type
when :start_element
tags.push p_e[0]
results << "<#{tags.last}#{attrs_to_s(p_e[1])}>"
when :end_element
results << "</#{tags.pop}>"
when :text
results << p_e[0][0..new_len]
new_len -= p_e[0].length
else
results << "<!-- #{p_e.inspect} -->"
end
end
if at_end
results << "..."
end
tags.reverse.each do |tag|
results << "</#{tag}>"
end
results
end
private
def attrs_to_s(attrs)
if attrs.empty?
''
else
' ' + attrs.to_a.map { |attr| %{#{attr[0]}="#{attr[1]}"} }.join(' ')
end
end
end
Here's a solution that works for me with Textile.
Convert it to HTML
Truncate it.
Remove any HTML tags that got cut in half with
html_string.gsub(/<[^>]*$/, "")
Then, uses Hpricot to clean it up and close unclosed tags
html_string = Hpricot( html_string ).to_s
I do this in a helper, and with caching there's no performance issue.
You could use a regular expression to find a line consisting of nothing but "^" characters:
markdown_string = <<-eos
This article is an example of something or other.
This segment will be used as the snippet on the index page.
^^^^^^^^^^^^^^^
This text will be visible once clicking the "Read more.." link
eos
preview = markdown_string[0...(markdown_string =~ /^\^+$/)]
puts preview
Rather than trying to truncate the text, why not have 2 input boxes, one for the "opening blurb" and one for the main "guts". That way your authors will know exactly what is being show when without having to rely on some sort of funkly EOF marker.
I will have to agree with the "two inputs" approach, and the content writer would need not to worry, since you can modify the background logic to mix the two inputs in one when showing the full content.
full_content = input1 + input2 // perhaps with some complementary html, for a better formatting
Not sure if it applies to this case, but adding the solution below for the sake of completeness. You can use strip_tags method if you are truncating Markdown-rendered contents:
truncate(strip_tags(markdown(article.contents)), length: 50)
Sourced from:
http://devblog.boonecommunitynetwork.com/rails-and-markdown/
A simpler option that just works:
truncate(markdown(item.description), length: 100, escape: false)