in crates/core/src/expr/mod.rs [80:91]
fn from_str(s: &str) -> Result<Self, Self::Err> {
ExprOperator::TOKEN_OP_PAIRS
.iter()
.find_map(|&(token, op)| {
if token.eq_ignore_ascii_case(s) {
Some(op)
} else {
None
}
})
.ok_or_else(|| Unsupported(format!("Unsupported operator: {}", s)))
}