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Diffstat (limited to 'clap/examples/10_default_values.rs')
| -rw-r--r-- | clap/examples/10_default_values.rs | 40 |
1 files changed, 0 insertions, 40 deletions
diff --git a/clap/examples/10_default_values.rs b/clap/examples/10_default_values.rs deleted file mode 100644 index ca50981..0000000 --- a/clap/examples/10_default_values.rs +++ /dev/null @@ -1,40 +0,0 @@ -extern crate clap; - -use clap::{App, Arg}; - -fn main() { - // There are two ways in which to get a default value, one is to use claps Arg::default_value - // method, and the other is to use Rust's built in Option::unwrap_or method. - // - // I'll demo both here. - // - // First, we'll use clap's Arg::default_value with an "INPUT" file. - let matches = App::new("myapp").about("does awesome things") - .arg(Arg::with_name("INPUT") - .help("The input file to use") // Note, we don't need to specify - // anything like, "Defaults to..." - // because clap will automatically - // generate that for us, and place - // it in the help text - .default_value("input.txt") - .index(1)) - - // Next we'll use the Option::unwrap_or method on this "CONFIG" option - .arg(Arg::with_name("CONFIG") - // Note that we have to manually include some verbiage to the user - // telling them what the default will be. - .help("The config file to use (default is \"config.json\")") - .short("c") - .takes_value(true)) - .get_matches(); - - // It's safe to call unwrap because the value with either be what the user input at runtime - // or "input.txt" - let input = matches.value_of("INPUT").unwrap(); - - // Using Option::unwrap_or we get the same affect, but without the added help text injection - let config_file = matches.value_of("CONFIG").unwrap_or("config.json"); - - println!("The input file is: {}", input); - println!("The config file is: {}", config_file); -} |