Just had some requirements through for a query that a customer has specified.
“Set the value to 1 if the Outcome is not Complete or Cancelled or NULL”
This could be variously interpreted as:
“if the Outcome is NOT Complete and NOT Cancelled and NOT NULL”
Or “if the Outcome is NOT Complete, and NOT Cancelled, or IS NULL”
Or perhaps even “if the Outcome is NOT ‘Complete or Cancelled’ or IS NULL”
Obviously I’ll go back to them for clarity, but it’s a wonder why so often “bugs” arise based on interpretation of specifications.
Technical requirements are often ambiguous when written as free text, the way someone would speak them, because as you have discovered the free text fails to capture where the linguistic stress would be that disambiguates in speech.
Instead, I suggest using a format that is more suited to text.
I would recommend a table. Email the customer back with your current interpretation of the requirements, with a column for outcome and a column for value. Ask them to check and sign off on the table, or to correct the table where it is wrong.
Example:
Outcome Value NULL x Complete x Cancelled x (Other) x There are edge-cases with if outcome can be "Complete or Cncelled
Cheers yeah, that is standard usually. I was just having a whinge rather than asking for a solution. In this case the customer was trying to preempt having to complete a change request form (similar to what you’ve described) and get the relevant sign off etc, and had emailed over a “minor alteration” to an existing request, for which they should know better at this stage of the project.
Haha yeah, fair enough. Applogies for turning your deserved whinge into a serious question.
Wrangling annoying customers is always the most annoying part of the job isn’t it. How nice it would be to spend more time programming…
Even using bullet points can help a lot in these situations (I use them quite often in emails with non-technical recipients).
This helps with writing unit tests as well.
Don’t forget to ask what is the other possible value(s) if the scenario doesn’t happen, because that is something forgotten most of the time.
Completely agree, requirements are key and often badly defined due to the customers’ lack of knowledge of the intricacies of the system. You are correct to ask for clarity or it could come back to bite you later on.
I’ve just had a spec through from a BA which consists entirely of screenshots of an existing system with no technical definitition of any of the requested fields so relate to this right now.
What’s the difference between case 2 and 3? Those look the same to me. The three cases look like:
- ¬complete ∧ ¬cancelled ∧ ¬null
- (¬complete ∧ ¬cancelled) ∨ null
- ¬(complete ∨ cancelled) ∨ null
Case 3 is one separate text string containing the words ‘Complete or Cancelled’ (hence the quotes).
Oh, I thought that was just a grouping
