https://www.hillelwayne.com/tags/decision-tables/ Recent content in Decision Tables on Hillel Wayne Hugo -- gohugo.io en-us Wed, 09 Sep 2020 00:00:00 +0000 https://www.hillelwayne.com/post/decision-table-patterns/ Wed, 09 Sep 2020 00:00:00 +0000 https://www.hillelwayne.com/post/decision-table-patterns/ Decision tables are easy, simple, and powerful. You can teach them in five minutes and write one in half that time. You can look at a table and understand what it’s saying, see if it matches your problem, and check for design flaws. So it’s kinda weird that there’s basically nothing about them online. I wrote an introduction a while back, but I want something a little more formal. So this post will reintroduce the core ideas in a more formal way and then talk about some of the techniques you can apply to make better tables. https://www.hillelwayne.com/requirements/ Mon, 15 Jul 2019 00:00:00 +0000 https://www.hillelwayne.com/requirements/ Many bugs are implementation errors: there is a mistake in the code that makes it not do what you wanted it to do. For example, you may have accidentally left out the “list is empty” case, or written a nonterminating function. You can identify it as “definitely wrong” for a given input. Most testing, in fact most writing on software correctness, deals primarily with implementation errors. Above that we have specification errors. https://www.hillelwayne.com/post/decision-tables/ Mon, 09 Jul 2018 00:00:00 +0000 https://www.hillelwayne.com/post/decision-tables/ I really like decision tables but they’ve fallen out of common knowledge. Let’s fix that. A decision table is a means of concisely representing branching and conditional computations. In the most basic form, you have some columns that represent the “inputs” as booleans and some columns that represent outputs and effects. It looks like this: A B C f(A, B, C) T T T 1 T T F 3 T F T 7 T F F “cucumber” F - - NullError - means that it doesn’t matter what the value is.