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Description
What's the problem this feature will solve?
Currently, pip-compile outputs to requirements.txt but I think that it's misleading as the output of the tool better maps to the concept of lockfiles (aka constraints in pip-speak).
Describe the solution you'd like
I'd like pip-tools to be consistent with its own recommendations to use pip install -c.
Alternative Solutions
..not doing so?
Additional context
Last year, I wrote this explanation about the misconceptions of pinning: #1326 (comment). And I figured that pip-tools itself is sending mixed messaging regarding what it does. I believe we can correct at least some of it.