#### 2.5.4 Configuration errors ¶

All errors in functions in the `(lepton config)` are reported using one of two keys:

1. File errors (e.g. “Access denied” or “File not found” are indicated with the `system-error` key.
2. All other errors are indicated using the `config-error` key.

When a `config-error` is signalled, `data` part of the error arguments is a list containing one of the following symbols:

`unknown-encoding`

  The text being parsed was in an unknown encoding.

`parse`

  The configuration data wass ill-formed.

`key-not-found`

  A requested configuration key was not found.

`group-not-found`

  A requested configuration group was not found.

`invalid-value`

  A configuration value could not be parsed into the requested format.