Commit 2025-10-24 15:50 f055b42e

feat(Topology): the topology generated by a family of spaces (#29341) Some categories of topological spaces are "convenient" in the sense that they have nice categorical properties (e.g. they have limits, colimits and are cartesian closed). This PR is the first in a series towards showing that delta generated spaces form a cartesian closed monoidal category (see https://github.com/joelriou/topcat-model-category/blob/852a514c1d955ab586507bcd5a7b5efb99c6c3df/TopCatModelCategory/Convenient/CartesianClosed.lean#L92 for the general result), and this result is part of my formalization effort towards the Quillen model category structure on simplicial sets. In this PR, given a family X of topological spaces, and a topological space Y, we introduce the X-generated topology on Y, which is coinduced by all continuous maps X i → Y. (Eventually, this will generalize previous works by Dagur Asgeirsson and Ben Eltschig about compactly/delta generated spaces in mathlib. At some point, their definitions will be refactored as particular cases of the definitions in this PR series.)