• Tomek =?ISO-8859-2?Q?Sowi=F1ski?= (3/3) Feb 10 2011 Is there a way to statically assert compilation of an expression failed ...
• bearophile (4/5) Feb 10 2011 I have asked something like this a lot of time ago, but I don't know a w...
• Tomek =?ISO-8859-2?Q?Sowi=F1ski?= (8/14) Feb 10 2011 y to do it. You are able to statically
• Andrej Mitrovic (19/19) Feb 10 2011 How's this?
• Andrej Mitrovic (19/19) Feb 10 2011 I've managed to screw up the colon placement though, here's a quick fix:
• Tomek =?ISO-8859-2?Q?Sowi=F1ski?= (5/28) Feb 11 2011 How does it help to find out that compilation tripped on a specific stat...
• Andrej Mitrovic (1/1) Feb 11 2011 I thought you were just looking for a static assert with a custom messag...
• bearophile (4/5) Feb 10 2011 Asking for new features in this newsgroup is not so useful. You may add ...
• Jonathan M Davis (11/14) Feb 10 2011 You mean like

Tomek =?ISO-8859-2?Q?Sowi=F1ski?= <just ask.me> writes:

Is there a way to statically assert compilation of an expression failed *with a
certain message*? I want to check my static asserts trip when they should.

-- 
Tomek

bearophile <bearophileHUGS lycos.com> writes:

Tomek Sowiñski:

 Is there a way to statically assert compilation of an expression failed *with
a certain message*? I want to check my static asserts trip when they should.

I have asked something like this a lot of time ago, but I don't know a way to
do it. You are able to statically assert that some code doesn't compile, but I
don't know how to assert that a certain message gets produced. You are asking
for a specific static catch :-)

Bye,
bearophile

Tomek =?ISO-8859-2?Q?Sowi=F1ski?= <just ask.me> writes:

bearophile napisa=B3:

 Is there a way to statically assert compilation of an expression failed=


 *with a certain message*? I want to check
 my static asserts trip when they should. =20

=20
 I have asked something like this a lot of time ago, but I don't know a wa=

y to do it. You are able to statically
 assert that some code doesn't compile, but I don't know how to assert tha=

t a certain message gets produced. You are
 asking for a specific static catch :-)

Static catch, yeah. But I'd be content with traits__(fails, expr, msg) whic=
h seems tractable.

--=20
Tomek

Andrej Mitrovic <andrej.mitrovich gmail.com> writes:

How's this?

import std.stdio;
import std.conv;

void staticAssert(alias exp, string message, string file = __FILE__,
int line = __LINE__)()
{
    static if (!exp)
    {
        pragma(msg, file ~ ":(" ~ to!string(line) ~ ") " ~
"staticAssert: " ~  to!string(message));
        assert(0);
    }
}

void main()
{
    enum x = false;
    staticAssert!(x, "Oh no we failed!");

    int y;
}

Andrej Mitrovic <andrej.mitrovich gmail.com> writes:

I've managed to screw up the colon placement though, here's a quick fix:

import std.stdio;
import std.conv;

void staticAssert(alias exp, string message, string file = __FILE__,
int line = __LINE__)()
{
    static if (!exp)
    {
        pragma(msg, file ~ "(" ~ to!string(line) ~ "): " ~
"staticAssert: " ~  to!string(message));
        assert(0);
    }
}

void main()
{
    enum x = false;
    staticAssert!(x, "Oh no we failed!");

    int y;
}

Tomek =?ISO-8859-2?Q?Sowi=F1ski?= <just ask.me> writes:

Andrej Mitrovic napisa=B3:

 I've managed to screw up the colon placement though, here's a quick fix:
=20
 import std.stdio;
 import std.conv;
=20
 void staticAssert(alias exp, string message, string file =3D __FILE__,
 int line =3D __LINE__)()
 {
     static if (!exp)
     {
         pragma(msg, file ~ "(" ~ to!string(line) ~ "): " ~
 "staticAssert: " ~  to!string(message));
         assert(0);
     }
 }
=20
 void main()
 {
     enum x =3D false;
     staticAssert!(x, "Oh no we failed!");
=20
     int y;
 }

How does it help to find out that compilation tripped on a specific static =
assertion?

--=20
Tomek

Andrej Mitrovic <andrej.mitrovich gmail.com> writes:

I thought you were just looking for a static assert with a custom message?

bearophile <bearophileHUGS lycos.com> writes:

Tomek S.:

 Static catch, yeah. But I'd be content with traits__(fails, expr, msg) which
seems tractable.

Asking for new features in this newsgroup is not so useful. You may add it to
bugzilla...

Bye,
bearophile

Jonathan M Davis <jmdavisProg gmx.com> writes:

On Thursday, February 10, 2011 16:12:01 Tomek Sowi=C5=84ski wrote:
 Is there a way to statically assert compilation of an expression failed
 *with a certain message*? I want to check my static asserts trip when they
 should.

You mean like

static assert(0, "We have a failure, Captain!");

If a static assert fails, it's obvious. Compilation fails. Now, if you're t=
rying=20
to assert something like that a particular template instantiation fails, th=
e use=20
static assert(!__traits(compiles, exp)); where exp is the expression being=
=20
tested.

=2D Jonathan M Davis