icydb-core 0.94.0

IcyDB — A schema-first typed query engine and persistence runtime for Internet Computer canisters
Documentation 
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use crate::db::{
    predicate::Predicate,
    sql_shared::{Keyword, SqlParseError, SqlTokenCursor},
};

// Parse OR chains with left-associative reduced SQL predicate semantics.
pub(in crate::db::predicate::parser::expression) fn parse_or_predicate(
    cursor: &mut SqlTokenCursor,
) -> Result<Predicate, SqlParseError> {
    let mut left = parse_and_predicate(cursor)?;
    while cursor.eat_keyword(Keyword::Or) {
        let right = parse_and_predicate(cursor)?;
        left = Predicate::Or(vec![left, right]);
    }

    Ok(left)
}

// Parse AND chains with stronger precedence than OR.
fn parse_and_predicate(cursor: &mut SqlTokenCursor) -> Result<Predicate, SqlParseError> {
    let mut left = parse_not_predicate(cursor)?;
    while cursor.eat_keyword(Keyword::And) {
        let right = parse_not_predicate(cursor)?;
        left = Predicate::And(vec![left, right]);
    }

    Ok(left)
}

// Parse unary NOT before falling through to one primary predicate atom.
fn parse_not_predicate(cursor: &mut SqlTokenCursor) -> Result<Predicate, SqlParseError> {
    if cursor.eat_keyword(Keyword::Not) {
        return Ok(Predicate::Not(Box::new(parse_not_predicate(cursor)?)));
    }

    crate::db::predicate::parser::expression::atom::parse_predicate_primary(cursor)
}