use zed_extension_api::{    self as zed, SlashCommand, SlashCommandArgumentCompletion, SlashCommandOutput,    SlashCommandOutputSection, Worktree,}; struct SlashCommandsExampleExtension; impl zed::Extension for SlashCommandsExampleExtension {    fn new() -> Self {        SlashCommandsExampleExtension    }     fn complete_slash_command_argument(        &self,        command: SlashCommand,        _args: Vec<String>,    ) -> Result<Vec<zed_extension_api::SlashCommandArgumentCompletion>, String> {        match command.name.as_str() {            "echo" => Ok(vec![]),            "pick-one" => Ok(vec![                SlashCommandArgumentCompletion {                    label: "Option One".to_string(),                    new_text: "option-1".to_string(),                    run_command: true,                },                SlashCommandArgumentCompletion {                    label: "Option Two".to_string(),                    new_text: "option-2".to_string(),                    run_command: true,                },                SlashCommandArgumentCompletion {                    label: "Option Three".to_string(),                    new_text: "option-3".to_string(),                    run_command: true,                },            ]),            command => Err(format!("unknown slash command: \"{command}\"")),        }    }     fn run_slash_command(        &self,        command: SlashCommand,        args: Vec<String>,        _worktree: Option<&Worktree>,    ) -> Result<SlashCommandOutput, String> {        match command.name.as_str() {            "echo" => {                if args.is_empty() {                    return Err("nothing to echo".to_string());                }                 let text = args.join(" ");                 Ok(SlashCommandOutput {                    sections: vec![SlashCommandOutputSection {                        range: (0..text.len()).into(),                        label: "Echo".to_string(),                    }],                    text,                })            }            "pick-one" => {                let Some(selection) = args.first() else {                    return Err("no option selected".to_string());                };                 match selection.as_str() {                    "option-1" | "option-2" | "option-3" => {}                    invalid_option => {                        return Err(format!("{invalid_option} is not a valid option"));                    }                }                 let text = format!("You chose {selection}.");                 Ok(SlashCommandOutput {                    sections: vec![SlashCommandOutputSection {                        range: (0..text.len()).into(),                        label: format!("Pick One: {selection}"),                    }],                    text,                })            }            command => Err(format!("unknown slash command: \"{command}\"")),        }    }} zed::register_extension!(SlashCommandsExampleExtension);