nushell/crates/nu-cli/src/evaluate/operator.rs
Jonathan Turner 7974e09eeb
Math operators (#1601)
* Add some math operations

* WIP for adding compound expressions

* precedence parsing

* paren expressions

* better lhs handling

* add compound comparisons and shorthand lefthand parsing

* Add or comparison and shorthand paths
2020-04-18 13:50:58 +12:00

75 lines
2.7 KiB
Rust

use crate::data::value;
use nu_protocol::hir::Operator;
use nu_protocol::{Primitive, ShellTypeName, UntaggedValue, Value};
use std::ops::Not;
pub fn apply_operator(
op: Operator,
left: &Value,
right: &Value,
) -> Result<UntaggedValue, (&'static str, &'static str)> {
match op {
Operator::Equal
| Operator::NotEqual
| Operator::LessThan
| Operator::GreaterThan
| Operator::LessThanOrEqual
| Operator::GreaterThanOrEqual => {
value::compare_values(op, left, right).map(UntaggedValue::boolean)
}
Operator::Contains => string_contains(left, right).map(UntaggedValue::boolean),
Operator::NotContains => string_contains(left, right)
.map(Not::not)
.map(UntaggedValue::boolean),
Operator::Plus => value::compute_values(op, left, right),
Operator::Minus => value::compute_values(op, left, right),
Operator::Multiply => value::compute_values(op, left, right),
Operator::Divide => value::compute_values(op, left, right),
Operator::In => table_contains(left, right).map(UntaggedValue::boolean),
Operator::And => match (left.as_bool(), right.as_bool()) {
(Ok(left), Ok(right)) => Ok(UntaggedValue::boolean(left && right)),
_ => Err((left.type_name(), right.type_name())),
},
Operator::Or => match (left.as_bool(), right.as_bool()) {
(Ok(left), Ok(right)) => Ok(UntaggedValue::boolean(left || right)),
_ => Err((left.type_name(), right.type_name())),
},
}
}
fn string_contains(
left: &UntaggedValue,
right: &UntaggedValue,
) -> Result<bool, (&'static str, &'static str)> {
match (left, right) {
(
UntaggedValue::Primitive(Primitive::String(l)),
UntaggedValue::Primitive(Primitive::String(r)),
) => Ok(l.contains(r)),
(
UntaggedValue::Primitive(Primitive::Line(l)),
UntaggedValue::Primitive(Primitive::String(r)),
) => Ok(l.contains(r)),
(
UntaggedValue::Primitive(Primitive::String(l)),
UntaggedValue::Primitive(Primitive::Line(r)),
) => Ok(l.contains(r)),
(
UntaggedValue::Primitive(Primitive::Line(l)),
UntaggedValue::Primitive(Primitive::Line(r)),
) => Ok(l.contains(r)),
_ => Err((left.type_name(), right.type_name())),
}
}
fn table_contains(
left: &UntaggedValue,
right: &UntaggedValue,
) -> Result<bool, (&'static str, &'static str)> {
let left = left.clone();
match right {
UntaggedValue::Table(values) => Ok(values.iter().any(|x| x.value == left)),
_ => Err((left.type_name(), right.type_name())),
}
}