From bb5431b545fb22e579615c4663b8520eb7d6e329 Mon Sep 17 00:00:00 2001
From: Tpt <thomaspt@hotmail.fr>
Date: Fri, 1 Oct 2021 22:07:09 +0200
Subject: [PATCH] Removes PlanExpression::In

Can be expressed with Or and Equals
---
 lib/src/sparql/eval.rs         | 25 -------------------------
 lib/src/sparql/plan.rs         |  7 -------
 lib/src/sparql/plan_builder.rs | 18 ++++++++++++++----
 3 files changed, 14 insertions(+), 36 deletions(-)

diff --git a/lib/src/sparql/eval.rs b/lib/src/sparql/eval.rs
index 15419ef5..f3d94637 100644
--- a/lib/src/sparql/eval.rs
+++ b/lib/src/sparql/eval.rs
@@ -992,31 +992,6 @@ impl SimpleEvaluator {
                     )
                 })
             }
-            PlanExpression::In(e, l) => {
-                let e = self.expression_evaluator(e);
-                let l: Vec<_> = l
-                    .iter()
-                    .map(|possible| self.expression_evaluator(possible))
-                    .collect();
-                Rc::new(move |tuple| {
-                    let needed = e(tuple)?;
-                    let mut error = false;
-                    for possible in &l {
-                        if let Some(possible) = possible(tuple) {
-                            if Some(true) == equals(&needed, &possible) {
-                                return Some(true.into());
-                            }
-                        } else {
-                            error = true;
-                        }
-                    }
-                    if error {
-                        None
-                    } else {
-                        Some(false.into())
-                    }
-                })
-            }
             PlanExpression::Add(a, b) => {
                 let a = self.expression_evaluator(a);
                 let b = self.expression_evaluator(b);
diff --git a/lib/src/sparql/plan.rs b/lib/src/sparql/plan.rs
index b5fa317b..6291ad43 100644
--- a/lib/src/sparql/plan.rs
+++ b/lib/src/sparql/plan.rs
@@ -216,7 +216,6 @@ pub enum PlanExpression {
     GreaterOrEqual(Box<Self>, Box<Self>),
     Less(Box<Self>, Box<Self>),
     LessOrEqual(Box<Self>, Box<Self>),
-    In(Box<Self>, Vec<Self>),
     Add(Box<Self>, Box<Self>),
     Subtract(Box<Self>, Box<Self>),
     Multiply(Box<Self>, Box<Self>),
@@ -400,12 +399,6 @@ impl PlanExpression {
                     e.add_maybe_bound_variables(set);
                 }
             }
-            PlanExpression::In(a, bs) => {
-                a.add_maybe_bound_variables(set);
-                for b in bs {
-                    b.add_maybe_bound_variables(set);
-                }
-            }
             PlanExpression::Exists(e) => {
                 e.add_maybe_bound_variables(set);
             }
diff --git a/lib/src/sparql/plan_builder.rs b/lib/src/sparql/plan_builder.rs
index 09086df6..e52811e4 100644
--- a/lib/src/sparql/plan_builder.rs
+++ b/lib/src/sparql/plan_builder.rs
@@ -363,10 +363,20 @@ impl<'a> PlanBuilder<'a> {
                 Box::new(self.build_for_expression(a, variables, graph_name)?),
                 Box::new(self.build_for_expression(b, variables, graph_name)?),
             ),
-            Expression::In(e, l) => PlanExpression::In(
-                Box::new(self.build_for_expression(e, variables, graph_name)?),
-                self.expression_list(l, variables, graph_name)?,
-            ),
+            Expression::In(e, l) => {
+                let e = self.build_for_expression(e, variables, graph_name)?;
+                l.iter()
+                    .map(|v| {
+                        Ok(PlanExpression::Equal(
+                            Box::new(e.clone()),
+                            Box::new(self.build_for_expression(v, variables, graph_name)?),
+                        ))
+                    })
+                    .reduce(|a: Result<_, EvaluationError>, b| {
+                        Ok(PlanExpression::Or(Box::new(a?), Box::new(b?)))
+                    })
+                    .unwrap_or_else(|| Ok(PlanExpression::Constant(false.into())))?
+            }
             Expression::Add(a, b) => PlanExpression::Add(
                 Box::new(self.build_for_expression(a, variables, graph_name)?),
                 Box::new(self.build_for_expression(b, variables, graph_name)?),