modules: add proper example

src/nix/target/modules.md

@@ -5,7 +5,34 @@ In Gleam, each module corresponds to a single `.gleam` file, and has its own exp
 When translated to Nix, **each Gleam module becomes a single Nix file.**
 For example, if your package is named `hello`, the file at `src/my/module.gleam` will generate a file `build/dev/nix/hello/my/module.nix` on build.
 
-Each module file **evaluates to an attribute set containing all exported names.** For example, a module with `pub type Type { Constr(a: Int, b: Int) }`, `pub fn fun()` and `pub const name: Int = 5` will evaluate to an attribute set with attributes `Constr`, `fun` and `name`.
+Each module file **evaluates to an attribute set containing all exported names.**
+
+For example, the module below:
+
+```gleam
+pub type Type {
+  Constructor(a: Int, b: Int)
+}
+
+pub const constant: Int = 5
+
+pub fn name() {
+  "Hello World!"
+}
+```
+
+transpiles to
+
+```nix
+let
+  Constructor = a: b: { __gleamTag = "Constructor"; inherit a b; };
+
+  name = { }: "Hello World!";
+
+  constant = 5;
+in
+{ inherit Constructor name constant; }
+```
 
 ## Prelude