## digitalmars.D.learn - Segfault using std.algorithm.map

• klickverbot (27/27) Oct 16 2010 As you might know from the main D NG, I have just started to solve a few...
• klickverbot (10/26) Oct 16 2010 Okay, after experimenting for a bit, I found that this works:
• klickverbot (2/2) Oct 16 2010 Forget it, I took this directly to bugzilla:
klickverbot <see klickverbot.at> writes:
```As you might know from the main D NG, I have just started to solve a few
little programming puzzles with D2/Phobos to test how well especially
the algorithm/range stuff in Phobos works out in more-or-less real world
use cases.

To solve a Caesar-cipher related challenge (from hacker.org, by the
way), I wrote up the following simple program:

---
import std.algorithm;
import std.stdio;

enum INPUT = "cqrb lryqna rb fjh, fjh qjamna cqjw axc cqracnnw. qnan,
hxd wnena twxf qxf oja cx bqroc! xq kh cqn fjh, cqn jwbfna rb
mnjmvjwblqnbc.";

void main() {
foreach ( offset; 0..25 ) {
writeln( map!( ( dchar c ) {
if ( c < 'a' ) return c;
if ( 'z' < c ) return c;
return cast( dchar )( ( ( ( c - 'a' ) + offset ) % 26 ) + 'a' );
} )( INPUT ) );
}
}
---

Seems reasonable, right? Using DMD 2.049, however, it segfaults in the
delegate literal. Why this? Have I missed something obvious?

If you don't want to compile it yourself, I have posted the backtrace
here: http://gist.github.com/630201

David
```
Oct 16 2010
klickverbot <see klickverbot.at> writes:
```On 10/16/10 10:13 PM, klickverbot wrote:
---
import std.algorithm;
import std.stdio;

enum INPUT = "cqrb lryqna rb fjh, fjh qjamna cqjw axc cqracnnw. qnan,
hxd wnena twxf qxf oja cx bqroc! xq kh cqn fjh, cqn jwbfna rb
mnjmvjwblqnbc.";

void main() {
foreach ( offset; 0..25 ) {
writeln( map!( ( dchar c ) {
if ( c < 'a' ) return c;
if ( 'z' < c ) return c;
return cast( dchar )( ( ( ( c - 'a' ) + offset ) % 26 ) + 'a' );
} )( INPUT ) );
}
}
---

Okay, after experimenting for a bit, I found that this works:

writeln( map!( ( c ){
return offset;
} )( INPUT ) );

While this segfaults:

writeln( map!( ( c ){
return cast( dchar )( offset );
} )( INPUT ) );

I guess this should go to bugzilla, right?
```
Oct 16 2010
klickverbot <see klickverbot.at> writes:
```Forget it, I took this directly to bugzilla:
http://d.puremagic.com/issues/show_bug.cgi?id=5064
```
Oct 16 2010