mirror of
https://github.com/clap-rs/clap
synced 2024-12-13 06:12:40 +00:00
85f541d789
Impact: - Binary size: 556.6 KiB to 578.4 KiB - build time: 6.4950 us (7% slower) - parse time: 7.7256 us - parse sc time: 8.1580 us (5% faster) Fixes #1041 Fixes #2150
92 lines
2.5 KiB
Rust
92 lines
2.5 KiB
Rust
use std::io::Write;
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use clap::Command;
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fn main() -> Result<(), String> {
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loop {
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let line = readline()?;
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let line = line.trim();
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if line.is_empty() {
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continue;
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}
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match respond(line) {
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Ok(quit) => {
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if quit {
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break;
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}
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}
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Err(err) => {
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write!(std::io::stdout(), "{}", err).map_err(|e| e.to_string())?;
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std::io::stdout().flush().map_err(|e| e.to_string())?;
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}
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}
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}
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Ok(())
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}
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fn respond(line: &str) -> Result<bool, String> {
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let args = shlex::split(line).ok_or("error: Invalid quoting")?;
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let matches = cli()
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.try_get_matches_from(&args)
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.map_err(|e| e.to_string())?;
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match matches.subcommand() {
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Some(("ping", _matches)) => {
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write!(std::io::stdout(), "Pong").map_err(|e| e.to_string())?;
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std::io::stdout().flush().map_err(|e| e.to_string())?;
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}
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Some(("quit", _matches)) => {
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write!(std::io::stdout(), "Exiting ...").map_err(|e| e.to_string())?;
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std::io::stdout().flush().map_err(|e| e.to_string())?;
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return Ok(true);
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}
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Some((name, _matches)) => unimplemented!("{}", name),
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None => unreachable!("subcommand required"),
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}
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Ok(false)
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}
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fn cli() -> Command {
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// strip out usage
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const PARSER_TEMPLATE: &str = "\
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{all-args}
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";
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// strip out name/version
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const APPLET_TEMPLATE: &str = "\
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{about-with-newline}\n\
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{usage-heading}\n {usage}\n\
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\n\
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{all-args}{after-help}\
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";
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Command::new("repl")
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.multicall(true)
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.arg_required_else_help(true)
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.subcommand_required(true)
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.subcommand_value_name("APPLET")
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.subcommand_help_heading("APPLETS")
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.help_template(PARSER_TEMPLATE)
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.subcommand(
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Command::new("ping")
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.about("Get a response")
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.help_template(APPLET_TEMPLATE),
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)
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.subcommand(
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Command::new("quit")
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.alias("exit")
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.about("Quit the REPL")
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.help_template(APPLET_TEMPLATE),
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)
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}
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fn readline() -> Result<String, String> {
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write!(std::io::stdout(), "$ ").map_err(|e| e.to_string())?;
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std::io::stdout().flush().map_err(|e| e.to_string())?;
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let mut buffer = String::new();
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std::io::stdin()
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.read_line(&mut buffer)
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.map_err(|e| e.to_string())?;
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Ok(buffer)
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}
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