string-concatenation

I am just starting to learn Ruby (first time programming), and have a basic syntactical question with regards to variables, and various ways of writing code. Chris Pine's "Learn to Program" taught me to write a basic program like this... num_cars_again= 2 puts 'I own ' + num_cars_again.to_s + ' cars.' This is fine, but then I stumbled across the tutorial on ruby.learncodethehardway.com, and was taught to write the same exact program like this... num_cars= 2 puts "I own #{num_cars} cars." They both output the same thing, but obviously option 2 is a much shorter way to do it. Is there any

How to concatenate string in Swift? In Objective-C we do like NSString *string = @"Swift"; NSString *resultStr = [string stringByAppendingString:@" is a new Programming Language"]; or NSString *resultStr=[NSString stringWithFormat:@"%@ is a new Programming Language",string]; But I want to do this in Swift-language. Fogmeister You can concatenate strings a number of ways: let a = "Hello" let b = "World" let first = a + ", " + b let second = "\(a), \(b)" You could also do: var c = "Hello" c += ", World" I'm sure there are more ways too. Bit of description let creates a constant. (sort of like an

Suppose I have the following snippet: $assoc = New-Object psobject -Property @{ Id = 42 Name = "Slim Shady" Owner = "Eminem" } Write-host $assoc.Id + " - " + $assoc.Name + " - " + $assoc.Owner I'd expect this snippet to show: 42 - Slim Shady - Eminem But instead it shows: 42 + - + Slim Shady + - + Eminem Which makes me think the + operator isn't appropriate for concatenating strings and variables. How should you approach this with PowerShell? Write-Host "$($assoc.Id) - $($assoc.Name) - $($assoc.Owner)" See the Windows PowerShell Language Specification Version 3.0 , p34, sub-expressions

What is the most efficient way to write the old-school: StringBuilder sb = new StringBuilder(); if (strings.Count > 0) { foreach (string s in strings) { sb.Append(s + ", "); } sb.Remove(sb.Length - 2, 2); } return sb.ToString(); ...in LINQ? Jorge Ferreira This answer shows usage of LINQ ( Aggregate ) as requested in the question and is not intended for everyday use. Because this does not use a StringBuilder it will have horrible performance for very long sequences. For regular code use String.Join as shown in the other answer Use aggregate queries like this: string[] words = { "one", "two",

I have a long string that doesn't fit the width of the screen. For eg. String longString = "This string is very long. It does not fit the width of the screen. So you have to scroll horizontally to read the whole string. This is very inconvenient indeed."; To make it easier to read, I thought of writing it this way - String longString = "This string is very long." + "It does not fit the width of the screen." + "So you have to scroll horizontally" + "to read the whole string." + "This is very inconvenient indeed."; However, I realized that the second way uses string concatenation and will create

I need to create a callback for <h:commandButton> while as a parameter I need to pass an argument that is string-concatenated with an external parameter id: I tried nesting an EL expression something like this: <h:commandButton ... action="#{someController.doSomething('#{id}SomeTableId')}" /> However this failed with an EL exception. What is a right syntax/approach to do this? BalusC If you're already on EL 3.0 (Java EE 7; WildFly, Tomcat 8, GlassFish 4, etc), then you could use the new += operator for this: <h:commandButton ... action="#{someController.doSomething(id += 'SomeTableId')}" /> If

I am working on a problem out of CTCI. The third problem of chapter 1 has you take a string such as 'Mr John Smith ' and asks you to replace the intermediary spaces with %20 : 'Mr%20John%20Smith' The author offers this solution in Python, calling it O(n): def urlify(string, length): '''function replaces single spaces with %20 and removes trailing spaces''' counter = 0 output = '' for char in string: counter += 1 if counter > length: return output elif char == ' ': output = output + '%20' elif char != ' ': output = output + char return output My question: I understand that this is O(n) in terms