Sha256: 201673ec133edd6d44fe5ecb1107525948c83b92674e72982e101d18860f96d2
Contents?: true
Size: 1.9 KB
Versions: 6
Compression:
Stored size: 1.9 KB
Contents
use super::static_id::StaticId;
use magnus::{exception::arg_error, Error, Symbol, Value};
use std::fmt::Display;
/// Represents an enum as a set of Symbols (using `StaticId`).
/// Each symbol maps to a value of the enum's type.
pub struct SymbolEnum<'a, T: Clone> {
what: &'a str,
mapping: Mapping<T>,
}
impl<'a, T: Clone> SymbolEnum<'a, T> {
pub fn new(what: &'a str, mapping: Vec<(StaticId, T)>) -> Self {
Self {
what,
mapping: Mapping(mapping),
}
}
/// Map a Magnus `Value` to the entry in the enum.
/// Returns an `ArgumentError` with a message enumerating all valid symbols
/// when `needle` isn't a valid symbol.
pub fn get(&self, needle: Value) -> Result<T, magnus::Error> {
let needle: Symbol = needle.try_convert().map_err(|_| self.error(needle))?;
let id = magnus::value::Id::from(needle);
self.mapping
.0
.iter()
.find(|(haystack, _)| *haystack == id)
.map(|found| found.1.clone())
.ok_or_else(|| self.error(*needle))
}
pub fn error(&self, value: Value) -> Error {
Error::new(
arg_error(),
format!(
"invalid {}, expected one of {}, got {:?}",
self.what, self.mapping, value
),
)
}
}
struct Mapping<T: Clone>(Vec<(StaticId, T)>);
/// Mimicks `Array#inpsect`'s output with all valid symbols.
/// E.g.: `[:s1, :s2, :s3]`
impl<T: Clone> Display for Mapping<T> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "[")?;
if let Some(((last, _), elems)) = self.0.split_last() {
for (id, _) in elems.iter() {
write!(f, ":{}, ", Symbol::from(*id).name().unwrap())?;
}
write!(f, ":{}", Symbol::from(*last).name().unwrap())?;
}
write!(f, "]")?;
Ok(())
}
}
Version data entries
6 entries across 6 versions & 1 rubygems