How to get a backtrace from a running Ruby process: Ruby 2.6 # First, find out the PID of your Ruby...
TL;DR {} binds stronger than do … end (as always in Ruby, special characters bind stronger than words) Demo
Pour color on your Rails console with awesome_print. Turn confusing long strings into formatted output. Have objects and classes...
I have no idea how it's supposed to work (or why the don't have a print CSS), but...
When you print out a HTML pages, all raster images (like PNGs) will appear aliased. This is because a printer...
ExpandAnimations is a LibreOffice/OpenOffice.org Impress extension to expand presentation animations before exporting to PDF. This way the exported PDF will...
Single step and slow motion for Cucumber scenarios can come in handy, especially in @javascript scenarios. # features/support/examiners.rb AfterStep('@slow_motion...
The colors in Rails log files are helpful when watching them but, since they are ANSI color codes like ^[[4...
When cucumber encounters a failing step in a @javascript feature, the selenium browser window instantly closes. Sometimes you do not...
Sometimes you want to use a vanilla Ruby method like a block. You can use Object#method to obtain a...
I believe that when WEBrick has trouble bringing up your Rails application, the WEBrick component that is supposed to print...
While it might seem trivial to implement an invoice that sums up items and shows net, gross and vat totals...
Note that converting from RGB to CMYK will usually degrade your colors because no exact mapping is possible. Anyway, this...
Use the PDF toolkit: sudo apt-get install pdftk To rotate page 1 by 90 degrees clockwise: pdftk in.pdf cat...
Pdfposter is a Python script that allows to convert large PDFs into a PDF with multiple pages that can be...
You can unpack a .tar.gz file into the current directory like this: tar -xzvf archive.tar.gz The options used are
This will install a printer called "PDF": sudo apt-get install cups-pdf Files will be put into ~/PDF/ without...
Sometimes PDF cucumber tests fail at the first test run and succeed at the second run. You can fix this...
Automatically convert bitmap images like JPEGs, GIFs and PNGs to the crisp, clean, scalable vector art of EPS, SVG, and...
The trick is this: send a low-resolution version of your image to the screen, and a high-resolution version...
The Ubuntu Documentation on LaTeX says, that the packages tetex are no longer supported. You can install the alternative texlive...
PhantomJS is a minimalistic headless WebKit. It has fast and native support for various web standards: DOM handling, CSS selector...
If you plan to insert an existing PDF into a new LaTeX document that you will compile to PDF, you...
If you run specs or your application and get an error like: ActionController::MissingFile in 'ProductsController#show, should render PDF...