Preambles

We can put arbitrary extra Dart or Rust code in the generated files. This feature is called Dart/Rust preamble.

Typical scenarios

This can be useful, for example:

• Import some extra dependency packages/crates in the generate code. (e.g. rust_preamble: "use some::Thing;")
• Suppress some rules of the linter. (e.g. dart_preamble: "// ignore_for_file: this_is_a_lint_rule")

Tricks

• In YAML, it is allowed to write down multi-line string literal (see example below)

Example

Suppose we have this in flutter_rust_bridge.yaml:

dart_preamble: |
  // ignore_for_file: this_is_a_lint_rule
  whatever_thing_here;
rust_preamble: |
  use some::Thing;
  also_whatever_thing_here;

Then the generated files will have such code pasted as-is on the top.