warning: unnecessary parentheses around closure body
   --> homotopy-core/src/collapse.rs:135:22
    |
135 |         .filter(|&e| (e.target() != keep))
    |                      ^                  ^
    |
    = note: `#[warn(unused_parens)]` (part of `#[warn(unused)]`) on by default
help: remove these parentheses
    |
135 -         .filter(|&e| (e.target() != keep))
135 +         .filter(|&e| e.target() != keep)
    |

warning: unnecessary parentheses around closure body
   --> homotopy-core/src/collapse.rs:158:22
    |
158 |         .filter(|&e| (e.source() != keep))
    |                      ^                  ^
    |
help: remove these parentheses
    |
158 -         .filter(|&e| (e.source() != keep))
158 +         .filter(|&e| e.source() != keep)
    |

warning: `homotopy-core` (lib) generated 2 warnings (run `cargo fix --lib -p homotopy-core` to apply 2 suggestions)
   Compiling homotopy-core v0.1.0 (/home/maximus/.env/extern/diagrammatic-semiotics/homotopy-rs/homotopy-core)
warning: unused import: `homotopy_core::common::Boundary`
 --> homotopy-core/examples/export_dim4.rs:4:5
  |
4 | use homotopy_core::common::Boundary;
  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default

warning: `homotopy-core` (example "export_dim4") generated 1 warning (run `cargo fix --example "export_dim4" -p homotopy-core` to apply 1 suggestion)
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.48s
     Running `target/debug/examples/export_dim4`
=== Searching for dimension 4 examples ===

--- lips() ---
lips: dim=4, size=1
  source dim=3

--- pants_unit() ---
pants_unit: dim=4, size=1
  source dim=3

--- algebraic_snake() ---
algebraic_snake: dim=3, size=1

=== Approach 1: Padded half_braid lifted to dim 4 ===
half_braid: dim=3, size=1
padded_3d: dim=3, size=2
padded_4d: dim=4, size=0

=== Approach 2: Pad lips() at dim 4 ===
padded_lips: dim=4, size=2
  (original lips size was 1, now 2)

=== Exporting padded_lips (dim 4 with identity cospan) ===
