Function: generate() 
ts
function generate<Options>(
   command, 
   entry, 
opts): Promise<string>;Generate the command usage.
Type Parameters 
| Type Parameter | Default type | 
|---|---|
Options extends ArgOptions | ArgOptions | 
Parameters 
| Parameter | Type | Description | 
|---|---|---|
command | null | string | usage generate command, if you want to generate the usage of the default command where there are target commands and sub-commands, specify null. | 
entry | Command<Options> | A entry command | 
opts | CommandOptions<Options> | A command options | 
Returns 
Promise<string>
A rendered usage.
