I am trying to make a program that asks for user input and checks if it is correct, however it is case sensitive so it would be great if you could explain to me how to make incase sensitive in Ruby,
Thanks!
I assume that what you mean by "case insensitive" is that even if the user types a capital letter, the letter printed back to the user will always be lowercase.
I'm not sure if the actual input entry can be made automatically lowercase.
However, if you'd like to simply convert all characters in the input string to their lowercase equivalents, you can:
puts "Type some capital letters - I dare you..."
input = gets
puts input.downcase
of course, the real answer is simply capitalString.downcase.
Related
I saw two ways to use gets, a simple form:
print 'Insert your name: '
name = gets()
puts "Your name is #{name}"
and a form that drew my attention:
print 'Insert your name: '
STDOUT.flush
name = gets.chomp
puts "Your name is #{name}"
The second sample looks like perl in using the flush method of the default output stream. Perl makes explicit default output stream manipulating; the method flush is a mystery to me. It can behave different from what I'm inferring, and it uses chomp to remove the new line character.
What happens behind the scenes in the second form? What situation is it useful or necessary to use the second form?
"Flushing" the output ensures that it shows the printed message before it waits for your input; this may be just someone being certain unnecessarily, or it may be that on certain operating systems you need it. Alternatively you can use STDOUT.sync = true to force a flush after every output. (You may wonder, "Why wouldn't I always use this?" Well, if your code is outputting a lot of content, repeatedly flushing it may slow it down.)
chomp removes the newline from the end of the input. If you want the newline (the result of the user pressing "Enter" after typing their name) then don't chomp it.
Looking at some Github code I can see that STDOUT.flush is used mostly for server-side/multi-threaded jobs, and not in everyday use.
Generally speaking, when you want to accept input from the user, you'd want to use gets.chomp. Just remember, no matter what the user enters, Ruby will ALWAYS interprete that as a string.
To convert it to an integer, you need to call to_i, or to_f for a float. You don't need chomp in these cases, since to_i or to_f removes the "\n" automatically. There are a lot of subtle things going on implicitly as you'll see, and figuring them out is simply a matter of practice.
I've rarely seen someone use STDOUT.flush except in mutli-threading. Also it makes things confusing, defeating the whole purpose of writing elegant code.
I am writing a short LC-3 program to ask the user to input their name and print it out.
It should be something like this......
What is your name?
abcd
Hi abcd, nice to meet you!
But I got this one in the output......
What is your name?
abcd
Hi abcd
, nice to meet you!
I created 2 .STRINGZ for the sentences,
"Hi " as String1 and ", have a good day." as Strings2,
but how can I put the sentence ", have a good day." after the user name ?
Thanks
You haven't given us much to go on, some code would be nice (at least the relevant parts). However, just from what you posted... my guess would be that you are storing the characters as they are being entered, and at some point checking to see if one of those keystrokes is the "enter" key. It seems like you may be storing what's typed before checking for the enter key. Thus when the result is printed out, it's printing exactly what was typed, "abcd[enter]", which is causing the linefeed to print out also.
The easy solution is to move the piece of code where you check for the enter key before the code which stores what is entered, such that the enter key isn't stored also.
Sorry I couldn't be more helpful... but this is just my best guess based on the info given.
I am doing some localization testing and I have to test for strings in both English and Japaneses. The English string might be 'Waiting time is {0} minutes.' while the Japanese string might be '待ち時間は{0}分です。' where {0} is a number that can change over the course of a test. Both of these strings are coming from there respective property files. How would I be able to check for the presence of the string as well as the number that can change depending on the test that's running.
I should have added the fact that I'm checking these strings on a web page which will display in the relevant language depending on the location of where they are been viewed. And I'm using watir to verify the text.
You can read elsewhere about various theories of the best way to do testing for proper language conversion.
One typical approach is to replace all hard-coded text matches in your code with constants, and then have a file that sets the constants which can be updated based on the language in use. (I've seen that done by wrapping the require of that file in a case statement based on the language being tested. Another approach is an array or hash for each value, enumerated by a variable with a name like 'language', which lets the tests change the language on the fly. So validations would look something like this
b.div(:id => "wait-time-message).text.should == WAIT_TIME_MESSAGE[language]
To match text where part is expected to change but fall within a predictable pattern, use a regular expression. I'd recommend a little reading about regular expressions in ruby, especially using unicode regular expressions in ruby, as well as some experimenting with a tool like Rubular to test regexes
In the case above a regex such as:
/Waiting time is \d+ minutes./ or /待ち時間は\d+分です。/
would match the messages above and expect one or more digits in the middle (note that it would fail if no digits appear, if you want zero or more digits, then you would need a * in place of the +
Don't check for the literal string. Check for some kind of intermediate form that can be used to render the final string.
Sometimes this is done by specifying a message and any placeholder data, like:
[ :waiting_time_in_minutes, 10 ]
Where that would render out as the appropriate localized text.
An alternative is to treat one of the languages as a template, something that's more limited in flexibility but works most of the time. In that case you could use the English version as the string that's returned and use a helper to render it to the final page.
I have some basic validations for usernames using regular expressions, something like [\w-_]+, and I want to add support for Korean alphabet, while still keeping the validation the same.
I don't want to allow special characters, such as {}[]!##$%^&*() etc., I just want to replace the \w with something that matches a given alphabet in addition to [a-zA-Z0-9].
Which means username like 안녕 should be valid, but not 안녕[].
I need to do this in Ruby 1.9.
try this:
[가-힣]+
This matches every character from U+AC00 to U+D7A3, which is probably enough for your interest. (I don't think you'll need old hangul characters and stuff)
You can test for invalid characters like this:
#encoding: utf-8
def valid_name?(name)
!name.match(/[^a-zA-Z0-9\p{Hangul}]/)
end
ar = %w(안녕 name 안녕[].)
ar.each{|name| puts "#{name} is #{valid_name?(name) ? "valid" : "invalid"}."}
# 안녕 is valid.
# name is valid.
# 안녕[]. is invalid.
I think you can replace \w by [:word:]
/^[[:word:]\-_]+$/ should work
Matching for invalid characters is your best option, because there are way too many valid Korean characters - it's technically an alphabet but computerized as one-character-per-syllable, and additionally there are thousands of Chinese loan characters (Hanja) which should also be valid.
I'm trying to find an elegant solution on how to convert something like this
ALL CAPS TEXT. "WHY ANYONE WOULD USE IT?" THIS IS RIDICULOUS! HELP.
...to regular-case. I could more or less find all sentence-starting characters with:
(?<=^|(\. \"?)|(! ))[A-Z] #this regex sure should be more complex
but (standard) Ruby neither allows lookbehinds, nor it is possible to apply .capitalize to, say, gsub replacements. I wish I could do this:
"mytext".gsub(/my(regex)/, '\1'.capitalize)
but the current working solution would be to
"mytext".split(/\. /).each {|x| p x.capitalize } #but this solution sucks
First of all, notice that what you are trying to do will only be an approximation.
You cannot correctly tell where the sentence boundaries are. You can approximate it as The beginning of the entire string or right after a period, question mark, or exclamation mark followed by spaces. But then, you will incorrectly capitalize "economy" in "U.S. economy".
You cannot correctly tell which words should be capitalized. For example, "John" will be "john".
You may want to do some natural language processing to give you a close-to-correct result in many cases, but these methods are only probablistically correct. You will never get a perfect result.
Understanding these limitations, you might want to do:
mytext.gsub(/.*?(?:[.?!]\s+|\z)/, &:capitalize)