[−][src]Crate structconf
StructConf is a derive macro to combine argument parsing from clap and config file parsing from rust-ini at compile time. For example:
use structconf::StructConf; #[derive(StructConf)] struct Config { // Option available in the config file and the arguments #[conf(help = "description for the argument parser.")] pub default: i32, // Specify where the options are available. #[conf(no_file)] pub args_opt: u8, #[conf(no_short, no_long)] pub conf_opt: Option<String>, #[conf(no_short, no_long, no_file)] pub ignored: bool, // Customize the names #[conf(short = "x", long = "renamed-opt", file = "my_opt", help = "custom names.")] pub renamed: String, // Inverse arguments #[conf(short = "n", long = "no_pancakes", help = "disable pancakes.")] pub pancakes: bool, // Custom default values #[conf(default = "123.45")] pub floating: f64, }
Any named struct that uses #[derive(StructConf)]
will have the methods
from structconf::StructConf
available.
Additional attributes can be added to its fields to customize how they are parsed:
General attributes
default = "..."
: a Rust expression that will be evaluated as a fallback value. For example,default = "1+2"
, ordefault = "String::from(\"hello\"")
. Otherwise, the value given bystd::default::Default
will be used, or in case the assigned type isOption<T>
*,None
.
* Note: the assigned type must be exactly Option<T>
for this to work.
std::option::Option<T>
won't work, for example.
Argument parser attributes
help = "..."
: the help message shown in the argument parser when--help
is used.long = "arg_name"
: a custom long argument name. Otherwise, it will be obtained directly from the field's name.do_something
will be--do-something
.no_long
: don't include the option as a long argument.short = "x"
: a custom short argument name (only made up of a single character). Otherwise, it will be obtained directly from the field's name.do_something
will be-d
.no_short
: don't include the option as a short argument.inverse_arg
: the argument value is the opposite. The assigned type must implementstd::ops::Not
. This is useful for arguments where the argument's value is negated:
use structconf::StructConf; #[derive(StructConf)] struct Bakery { #[conf(inverse_arg, no_short, long = "--no-pancakes")] pancakes: bool }
If both no_long
and no_short
are provided, the option won't be
available in the argument parser at all.
Config file attributes
file = "..."
: a custom option name for the config file. Otherwise, it will be the same as the field's name.no_file
: son't include the option in the config file.section
: the section in the config file where the option will be. Otherwise,Default
is used. For example,#[structconf(section = "Planes")] model_id: i32
will look like this in the config file:
[Planes]
model_id = 123
Enums
Error | Small wrapper for the possible errors that may occur when parsing a StructConf-derived struct. |
Traits
StructConf | This trait implements the methods available after using
|
Derive Macros
StructConf |