Utilities for the swc project
# Cargo features
## `tty-emitter`
Adds default implementation of Emitter.
Enabling this feature will add tty-related dependencies.
## `sourcemap`
Adds methods to generate web sourcemap.
## `plugin-base`
Base mode for plugins, which can be enabled by `plugin-mode` or `plugin-rt`.
This mode creates a trait which can be used to override `swc_common` itself.
## `plugin-rt`
Creates an implementation for the plugin trait. This implements simply
invokes thread-locals declared in `swc_common`.
## `plugin-mode`
Allows replacing operations related to thread-local variables with a trait.
## `ahash`
Use `ahash` instead of `rustc_hash` for `AHashMap` and `AHashSet`.