September 2017 Update

Task/Sort-stability/Jq/sort-stability.jq

@@ -0,0 +1,5 @@
+[["UK", "London"],
+ ["US", "New York"],
+ ["US", "Birmingham"],
+ ["UK", "Birmingham"]]
+| sort_by(.[1])

Task/Sort-stability/OoRexx/sort-stability.rexx

@@ -0,0 +1,43 @@
+/* Rexx */
+Do
+  cities = .array~of('UK  London', 'US  New York', 'US  Birmingham', 'UK  Birmingham',)
+
+  Say; Say 'Original table'
+  Call display cities
+
+  Say; Say 'Unstable sort on city'
+  sorted = cities~copy
+  sorted~sortWith(.ColumnComparator~new(4, 20))
+  Call display sorted
+
+  Say; Say 'Stable sort on city'
+  sorted = cities~copy
+  sorted~stableSortWith(.ColumnComparator~new(4, 20))
+  Call display sorted
+
+  Say; Say 'Unstable sort on country'
+  sorted = cities~copy
+  sorted~sortWith(.ColumnComparator~new(1, 2))
+  Call display sorted
+
+  Say; Say 'Stable sort on country'
+  sorted = cities~copy
+  sorted~stableSortWith(.ColumnComparator~new(1, 2))
+  Call display sorted
+
+  Return
+End
+Exit
+
+display: Procedure
+Do
+  Use arg CT
+
+  Say '-'~copies(80)
+  Loop c_ over CT
+    Say c_
+    End c_
+
+  Return
+End
+Exit

Task/Sort-stability/Phix/sort-stability.phix

@@ -0,0 +1,25 @@
+sequence test = {{"UK","London"},
+                 {"US","New York"},
+                 {"US","Birmingham"},
+                 {"UK","Birmingham"}}
+
+---------------------
+-- probably stable --
+---------------------
+function cmp(object a, object b)
+    return compare(a[1],b[1])
+end function
+test = custom_sort(routine_id("cmp"),test)
+pp(test,{pp_Nest,1})
+
+-----------------------
+-- guaranteed stable --
+-----------------------
+function tag_cmp(integer i, integer j)
+    return compare({test[i][1],i},{test[j][1],j})
+--  return compare(test[i][1],test[j][1])
+end function
+sequence tags = custom_sort(routine_id("tag_cmp"),shuffle(tagset(4)))
+for i=1 to length(tags) do
+    ?test[tags[i]]
+end for

Task/Sort-stability/Rust/sort-stability.rust

@@ -0,0 +1,28 @@
+fn main() {
+    let country_city = vec![("UK", "London"),
+                            ("US", "New York"),
+                            ("US", "Birmingham"),
+                            ("UK", "Birmingham")];
+
+    let mut city_sorted = country_city.clone();
+    city_sorted.sort_by_key(|k| k.1);
+
+    let mut country_sorted = country_city.clone();
+    country_sorted.sort_by_key(|k| k.0);
+
+
+    println!("Original:");
+    for x in &country_city {
+        println!("{} {}", x.0, x.1);
+    }
+
+    println!("\nWhen sorted by city:");
+    for x in &city_sorted {
+        println!("{} {}", x.0, x.1);
+    }
+
+    println!("\nWhen sorted by county:");
+    for x in &country_sorted {
+        println!("{} {}", x.0, x.1);
+    }
+}

Task/Sort-stability/Zkl/sort-stability-1.zkl

@@ -0,0 +1,2 @@
+fcn sortByColumn(list,col)
+   { list.sort('wrap(city1,city2){ city1[col]<city2[col] }) }

Task/Sort-stability/Zkl/sort-stability-2.zkl

@@ -0,0 +1,5 @@
+cities:=List(
+   T("UK",  "London"), T("US",  "New York"),
+   T("US",  "Birmingham"),T("UK",  "Birmingham"), );
+sortByColumn(cities,0).concat("\n").println("\n------");
+sortByColumn(cities,1).concat("\n").println();