Just another update

Task/Substring/00DESCRIPTION

@@ -1,4 +1,6 @@
-{{basic data operation}}In this task display a substring:
+{{basic data operation}}
+[[Category:String manipulation]] [[Category:Simple]]
+In this task display a substring:
 
 * starting from <tt>n</tt> characters in and of <tt>m</tt> length;
 * starting from <tt>n</tt> characters in, up to the end of the string;
@@ -6,4 +8,6 @@
 * starting from a known character within the string and of <tt>m</tt> length;
 * starting from a known substring within the string and of <tt>m</tt> length.
 
-If the program uses UTF-8 or UTF-16, it must work on any valid Unicode code point, whether in the Basic Multilingual Plane or above it. The program must reference logical characters (code points), not 8-bit code units for UTF-8 or 16-bit code units for UTF-16. Programs for other encodings (such as 8-bit ASCII, or EUC-JP) are not required to handle all Unicode characters.
+If the program uses UTF-8 or UTF-16, it must work on any valid Unicode code point,
+whether in the Basic Multilingual Plane or above it.
+The program must reference logical characters (code points), not 8-bit code units for UTF-8 or 16-bit code units for UTF-16. Programs for other encodings (such as 8-bit ASCII, or EUC-JP) are not required to handle all Unicode characters.

Task/Substring/00META.yaml

@@ -1,4 +1,2 @@
 ---
-category:
-- String manipulation
 note: Basic language learning

Task/Substring/Go/substring-1.go

@@ -0,0 +1,26 @@
+package main
+
+import (
+    "fmt"
+    "strings"
+)
+
+func main() {
+    s := "ABCDEFGH"
+    n, m := 2, 3
+    // for reference
+    fmt.Println("Index: ", "01234567")
+    fmt.Println("String:", s)
+    // starting from n characters in and of m length
+    fmt.Printf("Start %d, length %d:    %s\n", n, m, s[n : n+m])
+    // starting from n characters in, up to the end of the string
+    fmt.Printf("Start %d, to end:      %s\n", n, s[n:])
+    // whole string minus last character
+    fmt.Printf("All but last:         %s\n", s[:len(s)-1])
+    // starting from a known character within the string and of m length
+    dx := strings.IndexByte(s, 'D')
+    fmt.Printf("Start 'D', length %d:  %s\n", m, s[dx : dx+m])
+    // starting from a known substring within the string and of m length
+    sx := strings.Index(s, "DE")
+    fmt.Printf(`Start "DE", length %d: %s`+"\n", m, s[sx : sx+m])
+}

Task/Substring/Go/substring-2.go

@@ -0,0 +1,29 @@
+package main
+
+import (
+    "fmt"
+    "strings"
+)
+
+func main() {
+    s := "αβγδεζηθ"
+    r := []rune(s)
+    n, m := 2, 3
+    kc := 'δ'  // known character
+    ks := "δε" // known string
+    // for reference
+    fmt.Println("Index: ", "01234567")
+    fmt.Println("String:", s)
+    // starting from n characters in and of m length
+    fmt.Printf("Start %d, length %d:    %s\n", n, m, string(r[n:n+m]))
+    // starting from n characters in, up to the end of the string
+    fmt.Printf("Start %d, to end:      %s\n", n, string(r[n:]))
+    // whole string minus last character
+    fmt.Printf("All but last:         %s\n", string(r[:len(r)-1]))
+    // starting from a known character within the string and of m length
+    dx := strings.IndexRune(s, kc)
+    fmt.Printf("Start %q, length %d:  %s\n", kc, m, string([]rune(s[dx:])[:m]))
+    // starting from a known substring within the string and of m length
+    sx := strings.Index(s, ks)
+    fmt.Printf("Start %q, length %d: %s\n", ks, m, string([]rune(s[sx:])[:m]))
+}

Task/Substring/Go/substring.go

@@ -1,14 +0,0 @@
-package main
-import "fmt"
-import "strings"
-
-func main() {
-  s := "ABCDEFGH"
-  n, m := 2, 3
-
-  fmt.Println(s[n:n+m]) // "CDE"
-  fmt.Println(s[n:]) // "CDEFGH"
-  fmt.Println(s[0:len(s)-1]) // "ABCDEFG"
-  fmt.Println(s[strings.Index(s, "D"):strings.Index(s, "D")+m]) // "DEF"
-  fmt.Println(s[strings.Index(s, "DE"):strings.Index(s, "DE")+m]) // "DEF"
-}

Task/Substring/Maple/substring-1.maple

@@ -0,0 +1,4 @@
+> n, m := 3, 5:
+> s := "The Higher, The Fewer!":
+> s[ n .. n + m - 1 ];
+                     "e Hig"

Task/Substring/Maple/substring-2.maple

@@ -0,0 +1,5 @@
+> s[ n .. -1 ] = s[ n .. ];
+ "e Higher, The Fewer!" = "e Higher, The Fewer!"
+
+> StringTools:-Drop( s, n - 1 );
+              "e Higher, The Fewer!"

Task/Substring/Maple/substring-3.maple

@@ -0,0 +1,5 @@
+> s[ 1 .. -2 ] = s[ .. -2 ];
+"The Higher, The Fewer" = "The Higher, The Fewer"
+
+> StringTools:-Chop( s );
+             "The Higher, The Fewer"

Task/Substring/Maple/substring-4.maple

@@ -0,0 +1,7 @@
+> pos := searchtext( ",", s ):
+> s[ pos .. pos + m - 1 ];
+                     ", The"
+
+> pos := searchtext( "Higher", s ):
+> s[ pos .. pos + m - 1 ];
+                     "Highe"

Task/Substring/Prolog/substring-1.pro

@@ -0,0 +1,17 @@
+substring_task(Str, N, M, Char, SubStr) :-
+    sub_string(Str, N, M, _, Span),
+    sub_string(Str, N, _, 0, ToEnd),
+    sub_string(Str, 0, _, 1, MinusLast),
+    string_from_substring_to_m(Str, Char, M, FromCharToMth),
+    string_from_substring_to_m(Str, SubStr, M, FromSubToM),
+    maplist( writeln,
+            [ 'from n to m ':Span,
+              'from n to end ': ToEnd,
+              'string minus last char ': MinusLast,
+              'form known char to m ': FromCharToMth,
+              'from known substring to m ': FromSubToM ]).
+
+
+string_from_substring_to_m(String, Sub, M, FromSubToM) :-
+    sub_string(String, Before, _, _, Sub),
+    sub_string(String, Before, M, _, FromSubToM).

Task/Substring/Prolog/substring-2.pro

@@ -0,0 +1,7 @@
+?- substring_task("abcdefghijk", 2, 4, "d", "ef").
+from n to m :cdef
+from n to end :cdefghijk
+string minus last char :abcdefghij
+form known char to m :defg
+from known substring to m :efgh
+true

Task/Substring/RPG/substring.rpg

@@ -0,0 +1,25 @@
+      *                                         1...5....1....5....2....5..
+     D myString        S             30    inz('Liebe bewegt das Universum!')
+     D output          S             30    inz('')
+     D n               S              2  0 inz(1)
+     D m               S              2  0 inz(5)
+     D length          S              2  0 inz(0)
+     D find            S              2  0 inz(0)
+
+      /free
+       *inlr = *on;
+        dsply    %subst(myString:n:m);
+        dsply    %subst(myString:7:20);
+
+        length = %len(%trim(myString));
+        dsply    %subst(myString:1:length-1);
+
+        find   = %scan('U':myString);
+        dsply    %subst(myString:find:9);
+
+        find   = %scan('bewegt':myString);
+        dsply    %subst(myString:find:%len('bewegt'));
+
+        output = ' *** end *** ';
+        dsply ' ' ' ' output;
+      /end-free

Task/Substring/Scala/substring.scala

@@ -6,14 +6,15 @@ object Substring {
 
   // Starting from n characters in and of m length
   assert("inspired by love" == str.slice(n, n + m))
+
   // Starting from n characters in, up to the end of the string
   assert("inspired by love and guided by knowledge." == str.drop(n))
+
   // Whole string minus last character
   assert("The good life is one inspired by love and guided by knowledge" == str.init)
+
   // Starting from a known character within the string and of m length
-  assert("life is one insp" == { val i = str.indexOf('l'); str.slice(i, i + m) })
-  // Alternatively
-  assert("life is one insp" == str.drop(str.indexOf('l')).take(m))
+  assert("life is one insp" == str.dropWhile(_ != 'l').take(m) )
 
   // Starting from a known substring within the string and of m length
   assert("good life is one" == { val i = str.indexOf("good"); str.slice(i, i + m) })