whereexpr 0.1.2

A fast, expressive rule-based filtering engine for Rust that evaluates boolean expressions over any data structure
Documentation 
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use crate::types::{FromRepr, IntoValueKind};
use crate::Error;
use std::fmt::Debug;
use std::str::FromStr;
use crate::Value;

#[derive(Debug)]
pub(crate) struct ListSearch<T>
where
    T: Copy + Eq + FromStr + Debug + Ord + IntoValueKind + FromRepr,
{
    list: Vec<T>,
}

impl<T> ListSearch<T>
where
    T: Copy + Eq + FromStr + Debug + Ord + IntoValueKind + FromRepr,
{
    pub(crate) fn with_str_list(list: &[&str]) -> Result<Self, Error> {
        let mut obj_list: Vec<T> = Vec::with_capacity(list.len());
        for s in list {
            let value = T::from_repr(s)?;
            obj_list.push(value);
        }
        if obj_list.is_empty() {
            return Err(Error::EmptyListForIsOneOf(<T>::VALUE_KIND));
        }
        obj_list.sort();
        obj_list.dedup();
        Ok(Self { list: obj_list })
    }
    pub(crate) fn with_value_list<'a, V>(list: &[V]) -> Result<Self, Error>
    where
        T: TryFrom<Value<'a>, Error=Error>,
        V: Into<Value<'a>> + Clone,
    {
        let mut obj_list: Vec<T> = Vec::with_capacity(list.len());
        for value in list {
            let value = T::try_from(value.clone().into())?;
            obj_list.push(value);
        }
        obj_list.sort();
        obj_list.dedup();
        Ok(Self { list: obj_list })
    }
    #[inline(always)]
    pub(crate) fn evaluate(&self, value: T) -> bool {
        if self.list.len() <= 8 {
            self.list.contains(&value)
        } else {
            self.list.binary_search(&value).is_ok()
        }
    }
}