remove any leading white space (tabs, spaces, and new lines) in ruby

To remove any leading white spaces (tabs, spaces, and new lines) from a string in Ruby, we can use a regular expression with the sub method. The regular expression matches any leading white spaces and replaces them with an empty string. Here is an example:

main.rb
str = "   hello world"
str.sub(/^\s+/, '')
43 chars
3 lines

In this example, the ^\s+ regular expression matches one or more leading white spaces at the beginning of the string. The sub method replaces the matched substring with an empty string.

After running this code, the value of str will be "hello world".