Sync

Task/Factorial/D/factorial.d

@@ -1,29 +1,29 @@
-import std.stdio, std.algorithm, std.metastrings, std.range;
+import std.stdio, std.algorithm, std.range;
 
-// iterative
-long factorial(long n) {
-    long result = 1;
+/// Iterative.
+int factorial(in int n) {
+    int result = 1;
     foreach (i; 1 .. n + 1)
         result *= i;
     return result;
 }
 
-// recursive
-long recFactorial(long n) {
+/// Recursive.
+int recFactorial(in int n) {
     if (n == 0)
         return 1;
     else
         return n * recFactorial(n - 1);
 }
 
-// functional-style
-long fact(long n) {
-    return iota(1, n + 1).reduce!q{a * b}();
+/// Functional-style.
+int fact(in int n) {
+    return iota(1, n + 1).reduce!q{a * b};
 }
 
-// tail recursive (at run-time, with DMD)
-long tfactorial(long n) {
-    static long facAux(long n, long acc) {
+/// Tail recursive (at run-time, with DMD).
+int tfactorial(in int n) {
+    static int facAux(int n, int acc) {
         if (n < 1)
             return acc;
         else
@@ -32,16 +32,16 @@ long tfactorial(long n) {
     return facAux(n, 1);
 }
 
-// computed and printed at compile-time
-pragma(msg, toStringNow!(factorial(15)));
-pragma(msg, toStringNow!(recFactorial(15)));
-pragma(msg, toStringNow!(fact(15)));
-pragma(msg, toStringNow!(tfactorial(15)));
+// Computed and printed at compile-time.
+pragma(msg, 15.factorial);
+pragma(msg, 15.recFactorial);
+pragma(msg, 15.fact);
+pragma(msg, 15.tfactorial);
 
 void main() {
-    // computed and printed at run-time
-    writeln(factorial(15));
-    writeln(recFactorial(15));
-    writeln(fact(15));
-    writeln(tfactorial(15));
+    // Computed and printed at run-time.
+    15.factorial.writeln;
+    15.recFactorial.writeln;
+    15.fact.writeln;
+    15.tfactorial.writeln;
 }