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Ingy döt Net 2013-10-27 22:24:23 +00:00
parent 6f050a029e
commit 776bba907c
3887 changed files with 59894 additions and 7280 deletions
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33
Task/Menu/D/menu.d
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@ -1,34 +1,35 @@
import std.stdio, std.conv, std.string, std.array;
import std.stdio, std.conv, std.string, std.array, std.typecons;
string menuSelect(in string[] entries) {
static int validChoice(in string input,
in int nEntries) pure nothrow {
static Nullable!(int, -1) validChoice(in string input,
in int nEntries)
pure nothrow {
try {
immutable n = to!int(input);
return (n >= 0 && n <= nEntries) ? n : -1;
} catch (Exception e) // very generic
return -1; // not valid
immutable n = input.to!int;
return typeof(return)((n >= 0 && n <= nEntries) ? n : -1);
} catch (Exception e) // Very generic
return typeof(return)(-1); // Not valid.
}
if (entries.empty)
return "";
while (true) {
writeln("Choose one:");
foreach (i, const string entry; entries)
"Choose one:".writeln;
foreach (immutable i, const entry; entries)
writefln(" %d) %s", i, entry);
writef("> ");
immutable input = readln().chomp();
immutable choice = validChoice(input, entries.length-1);
if (choice != -1)
return entries[choice]; // we have a valid choice
"> ".write;
immutable input = readln.chomp;
immutable choice = validChoice(input, entries.length - 1);
if (choice.isNull)
"Wrong choice.".writeln;
else
writeln("Wrong choice.");
return entries[choice]; // We have a valid choice.
}
}
void main() {
immutable items = ["fee fie", "huff and puff",
"mirror mirror", "tick tock"];
writeln("You chose '", menuSelect(items), "'.");
writeln("You chose '", items.menuSelect, "'.");
}