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Pre: Modify predicate implementation in preparation for functions that bind.

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Nick Alexander 2017-04-26 09:50:09 -07:00 committed by Richard Newman
parent 4d2eb7222e
commit 13e27c83e2
1 changed files with 3 additions and 5 deletions
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query-algebrizer/src/clauses/predicate.rs
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@ -30,15 +30,13 @@ use types::{
/// Application of predicates. /// Application of predicates.
impl ConjoiningClauses { impl ConjoiningClauses {
/// There are several kinds of predicates/functions in our Datalog: /// There are several kinds of predicates in our Datalog:
/// - A limited set of binary comparison operators: < > <= >= !=. /// - A limited set of binary comparison operators: < > <= >= !=.
/// These are converted into SQLite binary comparisons and some type constraints. /// These are converted into SQLite binary comparisons and some type constraints.
/// - A set of predicates like `fulltext` and `get-else` that are translated into
/// SQL `MATCH`es or joins, yielding bindings.
/// - In the future, some predicates that are implemented via function calls in SQLite. /// - In the future, some predicates that are implemented via function calls in SQLite.
/// ///
/// At present we have implemented only the five built-in comparison binary operators. /// At present we have implemented only the five built-in comparison binary operators.
pub fn apply_predicate<'s, 'p>(&mut self, schema: &'s Schema, predicate: Predicate) -> Result<()> { pub fn apply_predicate<'s>(&mut self, schema: &'s Schema, predicate: Predicate) -> Result<()> {
// Because we'll be growing the set of built-in predicates, handling each differently, // Because we'll be growing the set of built-in predicates, handling each differently,
// and ultimately allowing user-specified predicates, we match on the predicate name first. // and ultimately allowing user-specified predicates, we match on the predicate name first.
if let Some(op) = NumericComparison::from_datalog_operator(predicate.operator.0.as_str()) { if let Some(op) = NumericComparison::from_datalog_operator(predicate.operator.0.as_str()) {
@ -53,7 +51,7 @@ impl ConjoiningClauses {
/// - Ensures that the predicate functions name a known operator. /// - Ensures that the predicate functions name a known operator.
/// - Accumulates a `NumericInequality` constraint into the `wheres` list. /// - Accumulates a `NumericInequality` constraint into the `wheres` list.
#[allow(unused_variables)] #[allow(unused_variables)]
pub fn apply_numeric_predicate<'s, 'p>(&mut self, schema: &'s Schema, comparison: NumericComparison, predicate: Predicate) -> Result<()> { pub fn apply_numeric_predicate<'s>(&mut self, schema: &'s Schema, comparison: NumericComparison, predicate: Predicate) -> Result<()> {
if predicate.args.len() != 2 { if predicate.args.len() != 2 {
bail!(ErrorKind::InvalidNumberOfArguments(predicate.operator.clone(), predicate.args.len(), 2)); bail!(ErrorKind::InvalidNumberOfArguments(predicate.operator.clone(), predicate.args.len(), 2));
} }