Description
A basic argument parsing library for Grain inspired by the extremely popular minimist parser from the Node.js ecosystem.
Usage
In order to use Reaper copy the ./reaper.gr file into your project and use it like any other grain module, documentation can be found in ./reaper.md.
An example of how the library can be used is below, and a more apparent example can be found in ./example.gr.
Running the code below with grain example.gr -- --verbose -h will give the result:
Presence: ["a", "b", "help"]
Bools: [("verbose", true)]
Numbers: []
Ints: []
Strings: []
Multi: []
Rest: []
Passed Args: []
example.gr:
module ReaperExample
from "wasi/process" include Process
from "array" include Array
from "set" include Set
from "map" include Map
from "./reaper.gr" include Reaper
// Get the command line arguments
let args = match (Process.argv()) {
// Trim the runner binary or file (Different per wasm runtime)
Ok(args) => Array.slice(1, args),
// Note: Most likely a wasi permissions error
Err(_) => fail "Failed to read command line arguments",
}
// Parse the arguments
let options = Reaper.parse(
aliases=[> ("h", "help")],
presence=[> "help", "a", "b", "c"],
bools=[> "verbose", "bool"],
numbers=[> "float"],
ints=[> "int"],
strings=[> "string", "profile", "profile2"],
multi=[> "multi"],
args
)
// Print the parsed options
match (options) {
// Note: The arguments were parsed successfully
Ok(options) => {
print("Presence: " ++ toString(Set.Immutable.toList(options.presence)))
print("Bools: " ++ toString(Map.Immutable.toList(options.bools)))
print("Numbers: " ++ toString(Map.Immutable.toList(options.numbers)))
print("Ints: " ++ toString(Map.Immutable.toList(options.ints)))
print("Strings: " ++ toString(Map.Immutable.toList(options.strings)))
print("Multi: " ++ toString(Map.Immutable.toList(options.multi)))
print("Rest: " ++ toString(options.rest))
print("Passed Args: " ++ toString(options.passedArgs))
},
// Note: An unknown argument was given
Err(err) => fail Reaper.toStringError(err),
}