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Make sure you are in the directory that contains your Rails app, then create an app on Heroku. $ heroku create example Creating ⬢ example... done https://example.herokuapp.com/ | https://git.heroku.com/example.git The first URL of the ouput, http://example.herokuapp.com, is the location the ap...

Given these two CSV files: $ cat file1 1,line1 2,line2 3,line3 4,line4 $ cat file2 1,line3 2,line4 3,line5 4,line6 To print those lines in file2 whose second column occurs also in the first file we can say: $ awk -F, 'FNR==NR {lines[$2]; next} $2 in lines' file1 file2 1,line3 2,line4...

The -n flag enables you to check the syntax of a script without having to execute it: ~> $ bash -n testscript.sh testscript.sh: line 128: unexpected EOF while looking for matching `"' testscript.sh: line 130: syntax error: unexpected end of file

Download and install the WiX Toolset from wixtoolset.org. The installer for the WiX Toolset provides also the integration with Visual Studio, after the installation you should be able to create WiX specific projects. Warnings Admin rights are needed. Some versions of WiX are compatible only with...

Detailed instructions on getting asp.net-identity set up or installed.

The Gradle team works regularly on improving the performance of different aspects of Gradle builds. If you’re using an old version of Gradle, you’re missing out on the benefits of that work. Try upgrading to the latest version of Gradle to see what kind of impact it has. Doing so is low risk because...

If your routes file is overwhelmingly big, you can put your routes in multiple files and include each of the files with Ruby’s require_relative method: config/routes.rb: YourAppName::Application.routes.draw do require_relative 'routes/admin_routes' require_relative 'routes/sidekiq_routes' ...

Almost every function in C standard library returns something on success, and something else on error. For example, malloc will return a pointer to the memory block allocated by the function on success, and, if the function failed to allocate the requested block of memory, a null pointer. So you sho...

On Windows Download the Visual Studio Code installer for Windows. Once it is downloaded, run the installer (VSCodeSetup-version.exe). This will only take a minute. By default, VS Code is installed under C:\Program Files (x86)\Microsoft VS Code for a 64-bit machine. Note: .NET Framework 4.5.2...

String#at Returns a substring of a string object. Same interface as String#[]. str = "hello" str.at(0) # => "h" str.at(1..3) # => "ell" str.at(-2) # => "l" str.at(-2..-1) # => "lo" str.at(5) # => nil str.at(5..-...

String#to_time Converts a string to a Time value. The form parameter can be either :utc or :local, defaults to :local. "13-12-2012".to_time # => 2012-12-13 00:00:00 +0100 "06:12".to_time # => 2012-12-13 06:12:00 +0100 "2012-12-13 06...

String#exclude? The inverse of String#include? "hello".exclude? "lo" # => false "hello".exclude? "ol" # => true "hello".exclude? ?h # => false

String#squish Returns a version of the given string without leading or trailing whitespace, and combines all consecutive whitespace in the interior to single spaces. Destructive version squish! operates directly on the string instance. Handles both ASCII and Unicode whitespace. %{ Multi-line ...

String#pluralize Returns of plural form of the string. Optionally takes a count parameter and returns singular form if count == 1. Also accepts a locale parameter for language-specific pluralization. 'post'.pluralize # => "posts" 'octopus'.pluralize # => &quot...

When this program #include <stdio.h> #include <string.h> int main(void) { int num = 0; char str[128], *lf; scanf("%d", &num); fgets(str, sizeof(str), stdin); if ((lf = strchr(str, '\n')) != NULL) *lf = '\0'; printf("%d \"%s\&...

Say you want to add a foreign key company_id to the users table, and you want to have a NOT NULL constraint on it. If you already have data in users, you will have to do this in multiple steps. class AddCompanyIdToUsers < ActiveRecord::Migration def up # add the column with NULL allowed ...

const foobar = `foo bar` encoding := base64.StdEncoding encodedFooBar := make([]byte, encoding.EncodedLen(len(foobar))) encoding.Encode(encodedFooBar, []byte(foobar)) fmt.Printf("%s", encodedFooBar) // Output: Zm9vIGJhcg== Playground

str := base64.StdEncoding.EncodeToString([]byte(`foo bar`)) fmt.Println(str) // Output: Zm9vIGJhcg== Playground

encoding := base64.StdEncoding data := []byte(`Zm9vIGJhcg==`) decoded := make([]byte, encoding.DecodedLen(len(data))) n, err := encoding.Decode(decoded, data) if err != nil { log.Fatal(err) } // Because we don't know the length of the data that is encoded // (only the max length), we n...

decoded, err := base64.StdEncoding.DecodeString(`biws`) if err != nil { log.Fatal(err) } fmt.Printf("%s", decoded) // Output: n,, Playground