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Python Django REST Framework Make the REST Framework Work for You Overriding Generic View Methods

Posted by Hussein Almutawa
Hussein Almutawa
12,313 Points

When to use the ^ on urls.py and when not to?

So I noticed that in the urls.py file of the "Overriding Generic View Methods" workspaces that the 'course_detail' URL does not use a ^. All other URLs use a ^.

*So I have the following questions: 1) When is using a ^ necessary, and why use it? 2) Does order of URLs matter in the urlpatterns list?

*Please note that I have already taken the RegEx Python class, but can't seem to find the answer to those questions. Thank you!

2 Answers

hamsternation
hamsternation
26,616 Points
hamsternation
hamsternation
26,616 Points

The carat expression in regex represents where you want the search to start. the $ symbol is where you want the search to end.

for example, for a url(r'course', views.hello_world) entry in the urlpatterns, anything that has the word "course" in it as an url would direct you to the "hello_world" page... i.e.

mysite.com/somerandomcoursehere

mysite.com/courewaresforyou

mysite.com/course

mysite.com/ofcourse

adding the ^ and $ limits the regex to the characters in between, so url(r'^course/', views.hello_world) matches only when the user types mysite.com/course, which is what you want most of the time.

I hope that answers your question! :)