limbo/cli/docs/internal/commands.md

Cli Internal Docs

Repl Custom Commands Arg Parser

To distinguish between normal SQL queries and custom commands, we prefix a "." before our desired command. This signals to the to the REPL that you intend to use a custom command.

To implement this we use CLAP with multicall. It is very important we use multicall, else this will not work

Adding new Commands

To add new commands, we need to modify three places:

• commands/mod.rs
• commands/args.rs or create a new file under commands that will describe how you will use the Args for your command
• app.rs to handle the execution of the command

commands/mod.rs

   pub enum Command {
    ...
    /// Descriptive Message for your command
    Example(ExampleArgs),
   }

commands/args.rs

   #[derive(Debug, Clone, Args)]
    pub struct ExampleArgs {
        /// Example arg
        pub example: String,
    }

app.rs

    pub fn handle_dot_command(&mut self, line: &str) {
        ...
        Ok(cmd) => match cmd.command {
            ...
            Command::Example(args) => {
                println!("{}", args.example);
            }
        }
    }

Every single option that is available to CLAP is available here. To facilitate the creation of more helpful help messages, please use '///' in your args and command creation, so that CLAP can capture them in the codegen and create their descriptions.