From e4f3358fa81b8359fab2eb4dd3fb32e8eace8799 Mon Sep 17 00:00:00 2001
From: Elizabeth Mattijsen <liz@wenzperl.nl>
Date: Mon, 26 Jun 2017 01:04:19 +0200
Subject: [PATCH] Make Any (-) Map|Iterable about 2x faster

- because the right hand side no longer gets coerced to a Set first
- but instead is handled on-the-fly
- possibly without any iteration if the left is equivalent to an empty Set
---
 src/core/set_operators.pm | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/core/set_operators.pm b/src/core/set_operators.pm
index f5cbc0013df..af77c0d62f6 100644
--- a/src/core/set_operators.pm
+++ b/src/core/set_operators.pm
@@ -457,6 +457,9 @@ multi sub infix:<(-)>(Mixy:D $a, QuantHash:D $b) {
 multi sub infix:<(-)>(QuantHash:D $a, Mixy:D $b) {
     Rakudo::QuantHash.DIFFERENCE-MIXY-QUANTHASH($a.Mix, $b)
 }
+multi sub infix:<(-)>(Mixy:D $a, Map:D $b) {
+    Rakudo::QuantHash.DIFFERENCE-MIXY-QUANTHASH($a, $b.Set)
+}
 multi sub infix:<(-)>(Mixy:D $a, Any:D $b) {     # also Iterable
     Rakudo::QuantHash.DIFFERENCE-MIXY-QUANTHASH($a, $b.Set)
 }
@@ -475,12 +478,18 @@ multi sub infix:<(-)>(Baggy:D $a, QuantHash:D $b) {
 multi sub infix:<(-)>(QuantHash:D $a, Baggy:D $b) {
     Rakudo::QuantHash.DIFFERENCE-BAGGY-QUANTHASH($a.Bag, $b)
 }
+multi sub infix:<(-)>(Baggy:D $a, Map:D $b) {
+    Rakudo::QuantHash.DIFFERENCE-BAGGY-QUANTHASH($a, $b.Set)
+}
 multi sub infix:<(-)>(Baggy:D $a, Any:D $b) {    # also Iterable
     Rakudo::QuantHash.DIFFERENCE-BAGGY-QUANTHASH($a, $b.Set)
 }
 multi sub infix:<(-)>(Any:D $a, Baggy:D $b) {
     Rakudo::QuantHash.DIFFERENCE-BAGGY-QUANTHASH($a.Bag, $b)
 }
+multi sub infix:<(-)>(Any:D $a, Map:D $b)      { infix:<(-)>($a.Set, $b) }
+multi sub infix:<(-)>(Any:D $a, Iterable:D $b) { infix:<(-)>($a.Set, $b) }
+multi sub infix:<(-)>(Any:D $a, Any:D $b)      { infix:<(-)>($a.Set, $b.Set) }
 
 multi sub infix:<(-)>(**@p) {
     return set() unless @p;