2 releases (1 stable)
1.0.0 | Apr 29, 2024 |
---|---|
1.0.0-rc.1 | Apr 27, 2024 |
#1659 in Parser implementations
65 downloads per month
23KB
459 lines
Command Engine
Transform string instructions into code execution.
Engine
This crate provides a default engine, that is present if default features are enabled. It is simply a container for your Commands that can also execute them based on the input.
There are 2 versions of the default Engine:
sync
- Default.async
- Enabled withasync
feature.
Instruction
The given input is deserialized into a specific format defined in Instruction
structure.
It allows for one Command caller
, multiple positional args
, additional o_args
which act like flags
that can contain sub_args
.
Format:
<caller> <arg> <arg> --<o_arg> <sub_arg> <sub_arg> --<o_arg>
Example:
example argument1 argument2 --flag2 child1 child2 --flag3 --flag1
Deserializes to:
Instruction {
caller: "example",
args: vec!["argument1", "argument2"],
o_args: {
let mut map = HashMap::new();
map.insert("--flag2", Some(vec!["child1", "child2"]));
map.insert("--flag3", None);
map.insert("--flag1", None);
map
},
input: "example argument1 argument2 --flag2 child1 child2 --flag3 --flag1",
};
To add spaces in arguments use double quotes "
:
example "argument 1" "--flag 2" "child 1"
If there are double quotes in the argument it's suggested to use collector #
:
example #"argument "quotes" 1"#
There are no escape characters to avoid any heap allocations. Each argument is a string slice taken from the input.
Example
Sync version:
use command_engine::*;
pub struct Example;
impl CommandInfo for Example {
fn caller(&self) -> &'static str {
"ex"
}
}
impl Command for Example {
type Output = String;
fn on_execute(&self, ins: Instruction) -> Self::Output {
format!("{:?}", ins)
}
}
fn main() {
let input = "ex arg --o_arg sub_arg";
let mut engine = Engine::new();
engine.insert(Example);
// Will return formatted string of the Instruction.
let output = engine.execute(input).unwrap();
println!("{}", output);
}
Disclaimer
ToDo (in future):
- Custom Instructions (just like the Outputs)
- Integrated help command
Versioning:
*.*.*
- Released.*.*.*-rc.*
- Release Candidate.*.*.*-dev
- Unreleased in production.0.*.*
- Deprecated.
Dependencies
~0–1.1MB
~19K SLoC