On 17.08.2011 3:47, bearophile wrote:
Dmitry Olshansky:
To get a small no-crap-included beta package see download section of
https://github.com/blackwhale/FReD for .7zs.
I have not patched DMD, but it gives me some problem here:
void parseFlags(S)(S flags)
{
foreach(ch; flags)//flags are ASCII anyway
{
switch(ch)
{
foreach(i, op; __traits(allMembers, RegexOption))
{
case RegexOptionNames[i]:
if(re_flags& mixin("RegexOption."~op))
throw new RegexException(text("redundant flag
specified: ",ch));
re_flags |= mixin("RegexOption."~op);
break;
}
default:
if(__ctfe)
assert(text("unknown regex flag '",ch,"'"));
else
new RegexException(text("unknown regex flag '",ch,"'"));
}
To better see the situation I have written a small test case:
import std.typetuple: TypeTuple;
enum RegexOption : uint { A, B, C } // no need to put a semicolon here
alias TypeTuple!(RegexOption.A, RegexOption.B, RegexOption.C) RegexOptionNames;
void main() {
RegexOption ch;
switch (ch) {
foreach (i, op; __traits(allMembers, RegexOption))
case RegexOptionNames[i]: break;
default: assert(0);
}
}
test.d(12): Error: switch case fallthrough - use 'goto case;' if intended
test.d(12): Error: switch case fallthrough - use 'goto case;' if intended
test.d(12): Error: switch case fallthrough - use 'goto case;' if intended
test.d(14): Error: switch case fallthrough - use 'goto default;' if intended
This used to work, I think. The new DMD switch analysis seems to have a bug.
-------------
Yes, that's a bug. But it's not a regression, I assume you started to
compile with -w, that's when it happens IIRC. I almost forgot about it,
thanks for uncovering it again, you may as well file it.
If you want a benchmark, to compare it with other implementations, there is
this one:
http://shootout.alioth.debian.org/debian/program.php?test=regexdna&lang=gdc&id=4
All in due time, though this one involves semi-fixed patterns, hm ...
very promising.
--
Dmitry Olshansky
