kurisu-derive

Provides derive(Kurisu) for the Kurisu crate.

The Kurisu derive macro is not meant to do any validation nor display usage for the command line string values. It will only construct kurisu::Arg structs according to a given Rust Struct, and put them within a function get_info_instance wrapped by a oncecell static instance of a kurisu::Info_ struct.

Example: ```rust use kurisu::*;

[derive(Debug, Kurisu)]

struct Yargs { knots: usize, }

fn main() { let env_vars: Vec = std::env::args().skip(1).collect();

// The Derive Macro add `from_args` function to the user's struct,
// `from_args` will normalize the command line values into kurisu::Info.env_args
let args = Yargs::from_args(&env_vars);

let knots;
// This scope is so the mutex guard gets released after
// we retrieve the information we need.
{
    // The Derive Macro also add `get_info_instance` function to the user's struct.
    // The Kurisu:Info struct holds all the parsed information the Derive Macro did.
    let info = Yargs::get_info_instance(&env_vars).lock().unwrap();
    knots = info.args.iter().find(|a| a.name == "knots").unwrap().clone();
}

// If we assume the current example was called as follow: `mycli --knots 8`
// We would find that information within the Kurisu::Info struct
assert_eq!(info.env_args, vec!["--knots=8".to_string()]);
assert_eq!(knots.value, vec!["8".to_string()]);
assert_eq!(args.knots, 8);

} ```

Rust types with specific meaning

Type | Description --------------|--------------------------------------------- bool | Defines a Flag u8 | Defines a Flag with occurrence tracking as its value String | Defines value type of an Option or Argument PathBuf | Defines value type of an Option or Argument usize | Defines value type of an Option or Argument isize | Defines value type of an Option or Argument f64 | Defines value type of an Option or Argument Vec | Defines a repetitive Option or Argument

Override default behaviors on main Struct

The struct that drives these behaviors is handled by kurisu::Info, most of the annotation are associated to one of its field.

Field name | Default | Annotation | Description --------------|--------------|-------------------------|--------------------------------------------- name | "Unknown" | name = "mycli" | Change name on usage screen version | 0 | version = "0.1.0" | Change version on usage screen desc | None | desc = "some short text"| Change description on usage screen doc | None | /// | Change DISCUSSION text on usage screen allownoargs | false | allownoargs | Does not display usage screen if no command line values   |   | cargo | Will try to fetch name, version & desc from the Cargo.toml, the specific field annotation take precedence on the cargo annotation   |   | nosort | Avoid sorting alphabetically arguments, flags & options on usage screen   |   | auto_shorts | Enables the auto generation of short flags / options according to their field's name first letter, by default no short flags / options are generated unless specified on the struct's field annotation

Example: rust #[derive(Debug, Kurisu)] // Only picks the version from Cargo.toml since name & desc are already present #[kurisu(name = "yargs", cargo, desc = "some desc here", auto_shorts)] /// This text is for the DISCUSSION /// section in the use screen /// /// It can be a very large text struct Yargs {}

Override default behaviors on main Struct's fields

The struct that drives these behaviors is handled by kurisu::Arg, most of the annotation are associated to one of its field.

Field name | Default | Annotation | Description --------------|---------------|----------------------------|--------------------------------------------- vname | field's name | vname = "myname" | Change the name of the in the usage screen position | None | pos OR pos = "1" | Defines the position of an argument, pos without a value defines an infinite positional argument doc | None | /// | Defines the description of arg on the usage screen short | None | short OR short = "b" | Change the letter used by short flag / option, otherwise it takes the first letter of the struct's field name long | field's name | nolong OR long = "myname" | Change or remove the long flag / option env | field's name | env = "MYSQLHOST" | By default the field's name is used to look for environment variable match as last resort, this is to change which environment variable is being matched envprefix | None | envprefix = "MYSQL" | Will take the field's name and prefix it and look for a match environment variable requiredif | None | requiredif = "fieldname" | Will make this option required if the other flag/option is present default | "" | default = "42" | If not present in the command line values, struct field will be assigned this default value instead of default type value exit | None | exit = "myexitfunc" | Local function that triggers std::process::exit() after being executed. A bit like the usage display, it will stop execution at from_args   |   | parsewith = "myfunc" | Local function that allows custom parsing for this argument/flag/option

Example: ```rust use std::path::PathBuf;

[derive(Debug, Kurisu)]

struct Yargs { #[kurisu(pos = 1)] file: PathBuf, #[kurisu(pos)] // Infinite positional argument others: String, #[kurisu(short, nolong, envprefix = "MYSQL")] host: String, #[kurisu(long = "very-long-flag")] more: bool, /// description for crashed on usage screen crashed: bool, } ```