http://d.puremagic.com/issues/show_bug.cgi?id=4761
--- Comment #2 from bearophile_h...@eml.cc 2010-09-01 14:35:02 PDT --- A more general version: import std.traits: isArray, Unqual; /// ... T mul(T)(T items, int times) if(isArray!T) { alias Unqual!(typeof(items[0])) E; // dangerous? E[] result; static if(!is( typeof(items) == void[] )) { if (times > 0 && items.length > 0) { if (items.length == 1) { result.length = times; result[] = items[0]; } else { result.length = items.length * times; for (size_t pos; pos < result.length; pos += items.length) result[pos .. pos+items.length] = items[]; } } } return cast(T)result; // assumeUnique? } unittest { assert("".mul(-10) == ""); assert("".mul(0) == ""); assert("".mul(1) == ""); assert("".mul(10) == ""); assert("a".mul(-10) == ""); assert("a".mul(0) == ""); assert("a".mul(1) == "a"); assert("a".mul(10) == "aaaaaaaaaa"); assert("abc".mul(-10) == ""); assert("abc".mul(0) == ""); assert("abc".mul(1) == "abc"); assert("abc".mul(4) == "abcabcabcabc"); assert(""w.mul(-10) == ""w); assert(""w.mul(0) == ""w); assert(""w.mul(1) == ""w); assert(""w.mul(10) == ""w); assert("a"w.mul(-10) == ""w); assert("a"w.mul(0) == ""w); assert("a"w.mul(1) == "a"w); assert("a"w.mul(10) == "aaaaaaaaaa"w); assert("abc"w.mul(-10) == ""w); assert("abc"w.mul(0) == ""w); assert("abc"w.mul(1) == "abc"w); assert("abc"w.mul(4) == "abcabcabcabc"w); assert(""d.mul(-10) == ""d); assert(""d.mul(0) == ""d); assert(""d.mul(1) == ""d); assert(""d.mul(10) == ""d); assert("a"d.mul(-10) == ""d); assert("a"d.mul(0) == ""d); assert("a"d.mul(1) == "a"d); assert("a"d.mul(10) == "aaaaaaaaaa"d); assert("abc"d.mul(-10) == ""d); assert("abc"d.mul(0) == ""d); assert("abc"d.mul(1) == "abc"d); assert("abc"d.mul(4) == "abcabcabcabc"d); assert((new int[0]).mul(-10) == (new int[0])); assert((new int[0]).mul(0) == (new int[0])); assert((new int[0]).mul(1) == (new int[0])); assert((new int[0]).mul(10) == (new int[0])); assert([1].mul(-10) == (new int[0])); assert([1].mul(0) == (new int[0])); assert([1].mul(1) == [1]); assert([1].mul(5) == [1,1,1,1,1]); assert([1.5,2.3,3.1].mul(-10) == (new double[0])); assert([1.5,2.3,3.1].mul(0) == (new double[0])); assert([1.5,2.3,3.1].mul(1) == [1.5,2.3,3.1]); assert([1.5,2.3,3.1].mul(2) == [1.5,2.3,3.1,1.5,2.3,3.1]); const int[] a1; assert(a1.mul(-10) == a1); assert(a1.mul(0) == a1); assert(a1.mul(1) == a1); assert(a1.mul(10) == a1); const int[] a2 = [1]; assert(a2.mul(-10) == a1); assert(a2.mul(0) == a1); assert(a2.mul(1) == a2); assert(a2.mul(5) == [1,1,1,1,1]); const int[] a3 = [1, 2, 3]; assert(a3.mul(-10) == a1); assert(a3.mul(0) == a1); assert(a3.mul(1) == a3); assert(a3.mul(4) == [1,2,3,1,2,3,1,2,3,1,2,3]); static assert(is(typeof(a3.mul(4)) == const int[])); immutable int[] a4; assert(a4.mul(-10) == a4); assert(a4.mul(0) == a4); assert(a4.mul(1) == a4); assert(a4.mul(10) == a4); immutable int[] a5 = [1]; assert(a5.mul(-10) == a4); assert(a5.mul(0) == a4); assert(a5.mul(1) == a5); assert(a5.mul(5) == [1,1,1,1,1]); immutable int[] a6 = [1, 2, 3]; assert(a6.mul(-10) == a4); assert(a6.mul(0) == a4); assert(a6.mul(1) == a6); assert(a6.mul(4) == [1,2,3,1,2,3,1,2,3,1,2,3]); static assert(is(typeof(a6.mul(4)) == immutable int[])); immutable(int)[] a7 = [1, 2, 3]; static assert(is(typeof(a7.mul(0)) == immutable(int)[])); static assert(is(typeof(a7.mul(1)) == immutable(int)[])); static assert(is(typeof(a7.mul(3)) == immutable(int)[])); } void main() {} -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------