From dca04b00bc592e8e4b9e36234dccbc1c9531dfe3 Mon Sep 17 00:00:00 2001
From: trizen <trizen@protonmail.com>
Date: Sun, 2 Feb 2020 21:44:27 +0200
Subject: [PATCH] - Better performance in Array/Range `each_cons`.

---
 lib/Sidef/Types/Array/Array.pm | 26 +++++++++++++-------
 lib/Sidef/Types/Range/Range.pm | 24 +++++++++++++------
 scripts/Tests/slices_cons.sf   | 43 ++++++++++++++++++++++++++++++++++
 3 files changed, 78 insertions(+), 15 deletions(-)

diff --git a/lib/Sidef/Types/Array/Array.pm b/lib/Sidef/Types/Array/Array.pm
index 96932bc6c..bbd3f70b9 100644
--- a/lib/Sidef/Types/Array/Array.pm
+++ b/lib/Sidef/Types/Array/Array.pm
@@ -1398,13 +1398,18 @@ package Sidef::Types::Array::Array {
         $n = CORE::int($n);
 
         my @values;
+        my $count = 0;
 
         foreach my $item (@$self) {
-            CORE::push(@values, $item);
-            if (@values == $n) {
-                my @copy = @values;
+            if (++$count > $n) {
                 CORE::shift(@values);
-                $block->run(@copy);
+                --$count;
+            }
+
+            CORE::push(@values, $item);
+
+            if ($count == $n) {
+                $block->run(@values);
             }
         }
 
@@ -1420,13 +1425,18 @@ package Sidef::Types::Array::Array {
 
         my @result;
         my @values;
+        my $count = 0;
 
         foreach my $item (@$self) {
-            CORE::push(@values, $item);
-            if (@values == $n) {
-                my @copy = @values;
+            if (++$count > $n) {
                 CORE::shift(@values);
-                CORE::push(@result, $block->run(@copy));
+                --$count;
+            }
+
+            CORE::push(@values, $item);
+
+            if ($count == $n) {
+                CORE::push(@result, $block->run(@values));
             }
         }
 
diff --git a/lib/Sidef/Types/Range/Range.pm b/lib/Sidef/Types/Range/Range.pm
index f26dfecf7..84e7709c8 100644
--- a/lib/Sidef/Types/Range/Range.pm
+++ b/lib/Sidef/Types/Range/Range.pm
@@ -263,15 +263,21 @@ package Sidef::Types::Range::Range {
         $n > 0 or return $self;
 
         my @values;
-        my $iter = $self->iter;
+        my $count = 0;
+        my $iter  = $self->iter;
 
         for (; ;) {
             my $value = $iter->run() // last;
-            push @values, $value;
-            if (@values == $n) {
-                my @copy = @values;
+
+            if (++$count > $n) {
                 shift @values;
-                $block->run(@copy);
+                --$count;
+            }
+
+            push @values, $value;
+
+            if ($count == $n) {
+                $block->run(@values);
             }
         }
 
@@ -285,15 +291,19 @@ package Sidef::Types::Range::Range {
         $n > 0 or return $self;
 
         my @values;
-        my $iter = $self->iter;
+        my $count = 0;
+        my $iter  = $self->iter;
 
         for (; ;) {
             my $value = $iter->run() // do {
                 $block->run(@values) if @values;
                 return $self;
             };
+
             push @values, $value;
-            if (@values == $n) {
+
+            if (++$count == $n) {
+                $count = 0;
                 $block->run(splice(@values));
             }
         }
diff --git a/scripts/Tests/slices_cons.sf b/scripts/Tests/slices_cons.sf
index a8d12ca3f..30c0c409d 100644
--- a/scripts/Tests/slices_cons.sf
+++ b/scripts/Tests/slices_cons.sf
@@ -26,6 +26,34 @@ do {
     assert_eq(arr1, [[1, 2, 3], [7, 8, 9], [10]])
 }
 
+do {
+    var arr1 = []
+    var arr2 = []
+    r.each_slice(5, {|*a|
+        arr1 << a
+    })
+    a.each_slice(5, {|*a|
+        arr2 << a
+    })
+    assert_eq(arr1, arr2)
+    assert_eq(arr1, [[1, 2, 3, 4, 5], [6, 7, 8, 9, 10]])
+}
+
+do {
+    var arr1 = []
+    var arr2 = []
+    r.each_slice(3, {|*a|
+        arr1 << a
+        break if (a == [4,5,6])
+    })
+    a.each_slice(3, {|*a|
+        arr2 << a
+        break if (a == [4,5,6])
+    })
+    assert_eq(arr1, arr2)
+    assert_eq(arr1, [[1, 2, 3], [4, 5, 6]])
+}
+
 do {
     var arr1 = []
     var arr2 = []
@@ -41,6 +69,21 @@ do {
     assert_eq(arr1, [[1, 2, 3], [2, 3, 4], [3, 4, 5], [5, 6, 7], [6, 7, 8], [7, 8, 9], [8, 9, 10]])
 }
 
+do {
+    var arr1 = []
+    var arr2 = []
+    r.each_cons(3, {|*a|
+        arr1 << a
+        break if (a == [4,5,6])
+    })
+    a.each_cons(3, {|*a|
+        arr2 << a
+        break if (a == [4,5,6])
+    })
+    assert_eq(arr1, arr2)
+    assert_eq(arr1, [[1, 2, 3], [2, 3, 4], [3, 4, 5], [4, 5, 6]])
+}
+
 do {
     var arr1 = r.map_cons(3, {|*a|
         next if (a == [4,5,6])