docs: add note clarifying sigma / pi type naming convention discrepancy - #225
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docs: add note clarifying sigma / pi type naming convention discrepancy#225makabaka1880 wants to merge 1 commit into
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The terminology in the book might confuse those who are new to type theory.
Problem
External sources sometimes refer to the$\Sigma$ -type as the dependent sum type, whereas TPiL calls it the dependent product.
Solution
Added a line of prose for clarification at
book/TPiL/DependentTypeTheory.lean:1084Misc
Related zulip chat: here in channel #lean4