Merge pull request souffle-lang#1728 from mmcgr/astOutput

Print infix operators correctly from AST
joshuakarp · Nov 5, 2020 · fbb4c4b · fbb4c4b
2 parents 16293a9 + 8132bc8
commit fbb4c4b
Show file tree

Hide file tree

Showing 2 changed files with 20 additions and 1 deletion.
diff --git a/src/ast/BinaryConstraint.h b/src/ast/BinaryConstraint.h
@@ -83,7 +83,11 @@ class BinaryConstraint : public Constraint {
 
 protected:
     void print(std::ostream& os) const override {
-        os << *lhs << " " << operation << " " << *rhs;
+        if (isInfixFunctorOp(operation)) {
+            os << *lhs << " " << operation << " " << *rhs;
+        } else {
+            os << operation << "(" << *lhs << ", " << *rhs << ")";
+        }
     }
 
     bool equal(const Node& node) const override {

diff --git a/src/include/souffle/BinaryConstraintOps.h b/src/include/souffle/BinaryConstraintOps.h
@@ -412,6 +412,21 @@ inline bool isOrderedBinaryConstraintOp(const BinaryConstraintOp op) {
     UNREACHABLE_BAD_CASE_ANALYSIS
 }
 
+/**
+ * Determines whether a functor should be written using infix notation (e.g. `a + b + c`)
+ * or prefix notation (e.g. `+(a,b,c)`)
+ */
+inline bool isInfixFunctorOp(const BinaryConstraintOp op) {
+    switch (op) {
+        case BinaryConstraintOp::MATCH:
+        case BinaryConstraintOp::NOT_MATCH:
+        case BinaryConstraintOp::CONTAINS:
+        case BinaryConstraintOp::NOT_CONTAINS: return false;
+
+        default: return true;
+    }
+}
+
 /**
  * Get type binary constraint operates on.
  **/