mathlib

d13cc099 - feat(data/list/basic): add `list.length_filter_le` and `list.length_filter_map_le` (#15369)

feat(data/list/basic): add `list.length_filter_le` and `list.length_filter_map_le` (#15369) A `list` can't get longer when applying `list.filter` or `list.filter_map`. Co-authored-by: Junyan Xu <junyanxu.math@gmail.com> Co-authored-by: Kyle Miller <kmill31415@gmail.com> Co-authored-by: madvorak <dvorakmartinbridge@seznam.cz>