mx-naming — Invalid Module File or Directory Name

Severity: error | Blocks morph build: yes

What this error means

A source file or directory name violates the module naming gates, or two modules normalize to the same C++ namespace:

error : mx-naming : directory `Ledger` in `src/Ledger/list.mx` should be `ledger` (lowercase `[a-z0-9_]` only). Rename it.
  Learn more: https://morph.levizr.com/docs/errors/mx-naming

error : mx-naming : `src/Shop/item.mx` and `src/shop/item.mx` both normalize to `shop::item` — rename one.
  Learn more: https://morph.levizr.com/docs/errors/mx-naming

Why Morph raises it

Module paths become C++ namespaces mechanically: entry-relative segments, lowercased, [a-z0-9_] only (src/components/shop/ShopStore.mx → components::shop::shopstore). The rules exist because C++ namespaces cannot contain uppercase, dashes, or dots, and two files normalizing to one namespace would emit colliding symbols — a linker error pages away from its cause. Enforcing the gates at graph time keeps namespaces human-computable: you can predict the generated namespace from the path. Digit-leading segments are _-prefixed; anything outside the entry tree is rejected.

Example that triggers it

src/
  Ledger/            # ❌ should be `ledger`
    list.mx
  shop/
    Item.mx          # ❌ should be `item.mx`

Routes share the same source root, so shared components are fine:

src/
  add/
    route.mx         # ✅ `import NavBar from "../components/NavBar.mx"`
  components/
    NavBar.mx        # ✅ same `src/` tree — one namespace `components::navbar`

A file genuinely outside src/ is still rejected:

error : mx-naming : `shared/NavBar.mx` is outside the source tree `src` — move it under `src/`.
  Learn more: https://morph.levizr.com/docs/errors/mx-naming

How to fix

src/
  shop/            # ✅ lowercase, unique segments
    item.mx
  checkout/
    cart.mx

Rules:

• Directories and stems: lowercase [a-z0-9_] only (src/ledger, not src/Ledger; item.mx, not Item.mx).
• Every module in one build must live under the source root (src/). Routes (src/add/route.mx) and the entry (src/App.mx) share it, so ../components/… imports are in-tree.
• After lowercasing, every module path must be unique project-wide.
• Leading digits are _-prefixed automatically — avoid them where possible.

Steps:

1. Rename the flagged file/directory to lowercase with underscores.
2. Update every import that referenced the old path.
3. If the error is a collision, rename one of the two modules.
4. Re-run morph check.

Tuning this rule

Do not disable this rule. The gates protect namespace generation — violating names cannot produce valid C++.

See also

• mx-import-type — unsupported import kinds
• How a Morph Project Is Structured