@Override
    protected void derive(Schema schema) {
        fieldsSettingLanguage = fieldsSettingLanguage(schema);
        if (fieldsSettingLanguage.size() == 1) // Assume this language should be used for all fields
            addExpression(fieldsSettingLanguage.get(0).getIndexingScript());
        super.derive(schema);
    }
An indexing language script derived from a schema. An indexing script contains a set of indexing
statements, organized in a composite structure of indexing code snippets.

@author bratseth
config-model/src/main/java/com/yahoo/schema/derived/IndexingScript.java