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Sahar Nasiri
7,454 PointsUrls
I didn't get it! Why do we have to put our course_detail after step_detail?
1 Answer
David Lin
35,864 PointsI think it's due to Djano's use of regex pattern matching in the urls, so that the order in which a pattern is matched is important.
The course_detail url has one parameter, whereas the step_detail has two. The concern is that if course_detail with one parameter was used first, it would be sufficient to satisfy the regex pattern match criteria even if two parameters were present, thus, returning the course_detail instead of the step_detail if two parameters were present, which is incorrect.
On the other hand, by listing the step_detail first, the two-parameter regex pattern match will be used first to match, and return step_detail if two parameters are present. If not, then it will check if only one were present, and if so, return course_detail as expected.